Nasal mask system

ABSTRACT

A nasal cushion for a mask system includes a side wall defining a breathing chamber, an undercushion extending from the side wall, and a membrane that at least partially covers the undercushion. The membrane is adapted to seal along the nasal bridge, sides of nose, corners of nose, and upper lip of the patient&#39;s face in use. The undercushion is only provided along the side of nose, corner of nose, and upper lip regions of the cushion. The undercushion includes a flap or extending portion in each side of nose region that is wider than the other regions thereof and adapted to engage and provide a force into the sides of the patient&#39;s nose in use.

CROSS-REFERENCE TO APPLICATION

This application claims the benefit of U.S. Provisional Application Nos.61/213,326, filed May 29, 2009, 61/222,711, filed Jul. 2, 2009,61/272,162, filed Aug. 25, 2009, 61/272,250, filed Sep. 4, 2009,61/263,175, filed Nov. 20, 2009, and 61/282,693, filed Mar. 18, 2010,and Australian Provisional Application Nos. 2009902524, filed 2 Jun.2009, and 2009906101, filed 15 Dec. 2009, each of which is incorporatedherein by reference in its entirety. Australian Provisional ApplicationNo. (not yet known—attorney reference C10110), filed 28 May 2010, isalso incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to a nasal mask system used for treatment,e.g., of Sleep Disordered Breathing (SDB) with Continuous PositiveAirway Pressure (CPAP) or Non-Invasive Positive Pressure Ventilation(NIPPV).

BACKGROUND OF THE INVENTION

Patient interfaces, such as a full-face or nasal mask systems, for usewith blowers and flow generators in the treatment of Sleep DisorderedBreathing (SDB), typically include a soft face-contacting portion, suchas a cushion, and a rigid or semi-rigid shell or frame. In use, theinterface is held in a sealing position by headgear so as to enable asupply of air at positive pressure (e.g., 2-30 cm H₂O) to be deliveredto the patient's airways.

One factor in the efficacy of therapy and compliance of patients withtherapy is the comfort and fit of the patient interface.

The present invention provides alternative arrangements of mask systemsto enhance the efficacy of therapy and compliance of patients withtherapy.

SUMMARY OF THE INVENTION

One aspect of the present technology is to provide a mask system that issimple and unobtrusive. Another aspect of the present technology is amask system that can accommodate a wide range of different facial shapesincluding faces with high and low nasal bridge regions, and narrow andwide noses. Another aspect of the present technology is a mask systemwith a wide fit range.

A mask in accordance with the present technology is able to adapt therelative influence of different sealing forces dependent upon the sizeand shape of the face and nose of the wearer. In one form, an amount oftension force may be increased by splaying outwardly of an undercushion.

One aspect of the present technology is a cushion for a mask that sealsat its upper extent in a region of the nose that is generally close tothe junction between bone and cartilage on a range of people with largernoses, and which avoids impinging on the sight of people with smallernoses.

Another aspect of the present technology is a cushion for a mask thatincludes a thicker undercushion or backup band that supports a thinnermembrane or facial flap. In one form the cushion has an undercushion orbackup band that is relatively less stiff in an upper lip region than ina corner of the nose region, in a direction that is normal to the planeof the face of a person. In one form the cushion has no undercushion orbackup band in a nasal bridge region of the cushion. In one form theundercushion or backup band directs a sealing force against the sides ofthe nose in a nasal bridge region. In one form the cushion isconstructed and arranged so that when used by a person a relatively deepnasal bridge, the sides of the cushion in the region of the nasal bridgeare drawn inwards and the force on the side of the nose increases. Inone form, when used by a person with a relatively low nasal bridge, thesides of the cushion in the region of the nasal bridge splay outwards.In one form the undercushion is constructed and arranged to buckle. Inone form the undercushion has a C-shaped or a sickle-shapedcross-section.

In one form, a seal forming surface of a cushion in accordance with thepresent technology has a non-tacky surface. In one form a seal formingsurface of a cushion in accordance with the present technology has anon-polished surface. In one form, a seal forming surface of a cushionin accordance with the present technology has a frosted surface finish.

A cushion in accordance with the present technology is adapted to form aseal around a nose of a patient including a seal in a nasal bridgeregion of a patient. The nasal bridge region is a region of greatervariability between different patients than other regions of a nose.Another region of potential variability between faces is an angle of theforehead with respect to a plane of the face.

In order to accommodate a wide range of face shapes, a series of masksof different sizes and shapes may be constructed. However this may beexpensive. In accordance with the present technology, a cushion angleadjustment mechanism for a mask system may be provided to facilitaterotation or orientation of the cushion with respect to the plane of theface. In this way, a given mask system is able to accommodate a widerfit range of patients.

The cushion size and shape may be structured to accommodate a wide rangeof different facial shapes.

One aspect of the invention relates to a mask system including a frameadapted to attach headgear, a sealing arrangement releasably connectableto the frame, and an elbow provided to the sealing arrangement andadapted to be connected to an air delivery tube that delivers breathablegas to the patient. The sealing arrangement defines a breathing chamberand is adapted to form a seal with the patient's face. The sealingarrangement includes structure to establish a positive connection withthe frame and with the elbow.

Another aspect of the invention relates to a mask system including aframe and a sealing arrangement provided to the frame. The sealingarrangement includes a silicone cushion and a foam cushion provided tothe silicone cushion. The silicone cushion defines a breathing chamberand the foam cushion is supported by the silicone cushion such that thefoam cushion is not in communication with the breathing chamber. Thefoam cushion supports the sealing arrangement on the frame.

Another aspect of the invention relates to a mask system including aframe adapted to attach headgear and a sealing arrangement releasablyconnectable to the frame. The sealing arrangement defines a breathingchamber and is adapted to form a seal with the patient's face. Thesealing arrangement includes one or more protrusions adapted tointerlock with respective openings provided to the frame and providevisual reinforcement that the connection has been established.

Another aspect of the invention relates to a sealing arrangement for amask system including a side wall defining a breathing chamber, anundercushion curving outwards from the side wall and away from thebreathing cavity, and a membrane that at least partially covers theundercushion. The membrane extends from the undercushion and curvesinwards into the breathing cavity.

Another aspect of the invention relates to a mask system including aframe, a sealing arrangement releasably connectable to the frame, anelbow provided to the sealing arrangement and adapted to be connected toan air delivery tube that delivers breathable gas to the patient, and aforehead support provided to the frame. The sealing arrangement definesa breathing chamber and is adapted to form a seal with the patient'sface. The forehead support includes an elongated arm adapted to extendfrom the frame and an upper headgear connector adapted to attach upperheadgear straps. At least a portion of the arm may be constructed frommetal.

Another aspect of the invention relates to a vent assembly forexhausting gases from a mask including at least two vent arrays and aconnecting structure that joins the at least two vent arrays together.Each of the at least two vent arrays includes at least one vent holestructured to exhaust gas from the mask. The connecting structure has afirst position and a second position in which the at least two ventarrays are arranged at an angle offset from the at least two vent arrayswhen the connecting structure is in the first position.

Another aspect of the invention relates to a method for making a maskincluding molding a vent structure, inserting the vent structure into amold for a mask component, and molding the mask component over the ventstructure, wherein molding the mask component aligns the vent structuresto create air flow paths that reduce interference of exiting air streamsin use.

Another aspect of the invention relates to a nasal mask defining abreathing chamber for the delivery of a supply of gas at positivepressure to the airways of a patient. The nasal mask includes asidewall, and a cushion located adjacent the sidewall at a rear side ofthe nasal mask. A rearward sealing surface of the cushion has a contourin a top lip region that is formed with a concave curvature to have ashape that is complementary to a top lip region of a person. The contourof the rearward surface of the cushion is constructed and arranged toextend in use along respective left and right sides of the nose from anasal bridge region of a person located adjacent the joint between thenasal bone and the cartilage to respective left and right nasal cornerregions of a person adjacent the left and right naso-labial creases. Thecontour of the rearward sealing surface of the cushion is furtheradapted to extend along the top lip of a person from the left side ofthe nose to the right side of the nose. The cushion includes arelatively thick backup band formed from a resilient flexible materialand extending from the sidewall to form respective cantilevers in a toplip region, a corner region and a side of nose region of the cushion.The cantilevers each have a length and a thickness and the cantileversdefine respective lip region, corner region and side of nose regionstiffnesses. The corner region cantilever is stiffer than the top lipregion cantilever in a direction normal to the plane of the face. Thecushion further includes a relatively thin facial flap. The facial flapis inwardly curving and extends around the perimeter of the cushion todefine the rearward sealing surface of the cushion. An inner edge of thefacial flap defines an orifice through which a portion of a nose of thepatient passes in use.

Another aspect of the invention relates to a nasal mask defining abreathing chamber for the delivery of a supply of gas at positivepressure to the airways of a patient. The nasal mask includes asidewall, and a cushion located adjacent the sidewall at a rear side ofthe nasal mask. A rearward sealing surface of the cushion has a contourin a top lip region that is formed with a concave curvature to have ashape that is complementary to a top lip region of a person. The contourof the rearward surface of the cushion is constructed and arranged toextend in use along respective left and right sides of the nose from anasal bridge region of a person to respective left and right nasalcorner regions of a person. The contour of the rearward sealing surfaceof the cushion is further adapted to extend along the top lip of aperson from the left side of the nose to the right side of the nose. Thecushion includes a relatively thick backup band formed from a resilientflexible material and extending from the sidewall to form respectivecantilevers in a top lip region, a corner region and a side of noseregion of the cushion. The top lip region cantilever has a C-shapedcross-section. The cushion further includes a relatively thin facialflap. The facial flap is inwardly curving and extends around theperimeter of the cushion to define the rearward sealing surface of thecushion. An inner edge of the facial flap defines an orifice throughwhich a portion of a nose of the patient passes in use.

Another aspect of the invention relates to a nasal mask defining abreathing chamber for the delivery of a supply of gas at positivepressure to the airways of a patient. The nasal mask includes asidewall, and a cushion located adjacent the sidewall at a rear side ofthe nasal mask. A rearward sealing surface of the cushion has a contourin a top lip region that is formed with a concave curvature to have ashape that is complementary to a top lip region of a person. The contourof the rearward surface of the cushion is constructed and arranged toextend in use along respective left and right sides of the nose from anasal bridge region of a person to respective left and right nasalcorner regions of a person. The contour of the rearward sealing surfaceof the cushion is further adapted to extend along the top lip of aperson from the left side of the nose to the right side of the nose. Thecushion includes a relatively thin facial flap. The facial flap isinwardly curving and extends around the perimeter of the cushion todefine the rearward sealing surface of the cushion. An inner edge of thefacial flap defines an orifice through which a portion of a nose of thepatient passes in use. The cushion further includes a relatively thickbackup band formed from a resilient flexible material and extending fromthe sidewall to form respective cantilevers in a top lip region, acorner region and a side of nose region of the cushion. A length of theside of nose region cantilever is longer than a length of the cornerregion cantilever, and the side of nose region cantilever is constructedand arranged to provide a force in a direction approximately normal tothe side of the nose.

In one form the cushion and mask body are moulded in one piece.Preferably the cushion and adjacent sidewall are moulded in one piece.In this arrangement a more controlled and comfortable bending of theundercushion may be achieved.

Another aspect of the invention relates to a nasal cushion for a masksystem. The nasal cushion includes a side wall defining a breathingchamber, an undercushion extending from the side wall, and a membranethat at least partially covers the undercushion. The membrane is adaptedto seal along the nasal bridge, sides of nose, corners of nose, andupper lip of the patient's face in use. The undercushion is onlyprovided along the side of nose, corner of nose, and upper lip regionsof the cushion. The undercushion includes a flap or extending portion ineach side of nose region that is wider than the other regions thereofand adapted to engage and provide a force into the sides of thepatient's nose in use.

Another aspect of the invention relates to a nasal cushion for a masksystem. The nasal cushion includes a cushion perimeter providing aplurality of regions. Each region is specifically configured to sealalong or around the nose, and each region has characteristics that areat least partially determinative of the sealing force, stabilization,force distribution, comfort, and/or fit range provided by the cushion.

Another aspect of the invention relates to a forehead support for arespiratory mask including a forehead support arm structured to extendfrom a frame and a forehead support pad provided to the arm. Theforehead support pad includes upper headgear connectors adapted toengage upper headgear straps and a flexible region. The upper headgearconnectors are constructed of a first material and the flexible regionis constructed of a second material that is more flexible than the firstmaterial to allow adjustment of the distance of the forehead support padfrom the patient's forehead in use.

Another aspect of the invention relates to a headgear connector for arespiratory mask including a frame connection structured to extend froma frame and a connector provided to the frame connection. The frameconnection is constructed of a more rigid material to hold the shape ofthe connector and transmit headgear forces to the mask and the connectoris constructed of a more flexible material to facilitate engagement anddisengagement of headgear straps with the connector.

Another aspect of the invention relates to a vent for a respiratory maskincluding a stem, at least one branch extending from the stem, and avent array provided to the end of each branch. Each vent array includesa body and at least one vent hole through the body. The branches arespaced about the stem and/or the branches are angled with respect tostem to position the vent arrays such that they achieve diffuse exitingair flow streams.

Another aspect of the invention relates to an elbow for a respiratorymask including a mask connection end adapted to connect to the mask anda tube connection end adapted to connect to an air delivery tube. Themask connection end includes a first region constructed of a more rigidmaterial and a second region constructed of a more flexible material.The second region provides flexibility to one or more portions of themask connection end to enable engagement and disengagement of the elbowwith the mask and/or sealing of the elbow with the mask.

Further aspects of the invention are as set out in the claims.

Other aspects, features, and advantages of this invention will becomeapparent from the following detailed description when taken inconjunction with the accompanying drawings, which are a part of thisdisclosure and which illustrate, by way of example, principles of thisinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings facilitate an understanding of the variousexamples of this invention. In such drawings:

FIG. 1-1 is a perspective view of a nasal mask system according to anexample of the present invention;

FIG. 1-2 is an exploded perspective view of the nasal mask system ofFIG. 1-1 showing the frame, silicone cushion, elbow, and swivel ring;

FIG. 1-3 is a perspective view showing the cushion of the nasal masksystem of FIG. 1-1;

FIG. 1-4 is a cross-sectional view of the cushion of FIG. 1-3;

FIG. 1-5 is a perspective view of a cushion according to an example ofthe present invention;

FIG. 1-6 is a side view of the cushion of FIG. 1-5;

FIG. 1-7 is bottom view of the cushion of FIG. 1-5;

FIG. 1-8 is a front view of the cushion of FIG. 1-5;

FIG. 1-9 is a cross-section view through line 1-9-1-9 of FIG. 1-8;

FIG. 1-10 is a cross-section view through line 1-10-1-10 of FIG. 1-8;

FIG. 1-11 is a cross-section view through line 1-11-1-11 of FIG. 1-8;

FIG. 1-12 is a cross-section view through line 1-12-1-12 of FIG. 1-8;

FIG. 2-1 is a perspective view of a nasal mask system according toanother example of the present invention;

FIG. 2-2 is an exploded perspective view of the nasal mask system ofFIG. 2-1 showing the frame, foam cushion, silicone cushion, elbow, andswivel ring;

FIG. 2-3 is a perspective view showing the frame of the nasal masksystem of FIG. 2-1;

FIG. 2-4 is a perspective view showing the foam cushion, siliconecushion, elbow, and swivel ring of the nasal mask system of FIG. 2-1;

FIG. 2-5 is a cross-sectional view of the foam cushion, siliconecushion, elbow, and swivel ring of FIG. 2-4;

FIG. 2-6 is a cross-sectional view of the silicone cushion of the nasalmask system of FIG. 2-1;

FIG. 2-7 is a cross-sectional view of the silicone cushion and foamcushion of the nasal mask system of FIG. 2-1;

FIG. 2-8 is a side view of the silicone cushion and foam cushion of thenasal mask system of FIG. 2-1;

FIGS. 3-1 to 3-79 are schematic views of headgear strap arrangements andheadgear connection arrangements according to alternative examples ofthe present invention;

FIGS. 4-1 to 4-4 are schematic views of elbow to cushion connectionarrangements according to alternative examples of the present invention;

FIGS. 4-5 to 4-9 are schematic views of swivel to elbow connectionarrangements according to alternative examples of the present invention;

FIGS. 5-1 and 5-2 are isometric views of an alternative embodiment ofthe present invention;

FIG. 5-3 is a front view of an alternative embodiment of the presentinvention;

FIG. 5-4 is a rear view of an alternative embodiment of the presentinvention;

FIG. 5-5 is an alternative embodiment of the present invention in use;

FIG. 5-6 is a side view of an alternative embodiment of the presentinvention;

FIGS. 6-1 to 6-12(b) are schematic views of headgear connectionarrangements according to alternative examples of the present invention;

FIGS. 7-1 to 7-3 show various views of a mask system according to anembodiment of the present invention;

FIGS. 8-1 to 8-3 show various views of a lower headgear connector for aframe according to an embodiment of the invention;

FIGS. 8-4 and 8-5 show lower headgear connectors according toalternative embodiments;

FIG. 9-1 shows an elongated arm for a forehead support according to anembodiment of the invention;

FIGS. 9-2 and 9-3 show a mask system with an elongated arm for aforehead support according to another embodiment of the invention;

FIG. 9-4 shows a mask system with an elongated arm for a foreheadsupport according to another embodiment of the invention;

FIGS. 10-1 to 10-5 show various views of a forehead support according toan embodiment of the invention;

FIG. 10-6 shows a forehead support according to another embodiment ofthe invention;

FIG. 11-1 shows a cushion according to an embodiment of the invention;

FIGS. 11-2 to 11-9 show various views of a cushion according to anotherembodiment of the invention;

FIGS. 12-1 to 12-3 show various views of an elbow according to anembodiment of the invention;

FIGS. 12-4 to 12-8 show various views of an elbow according to anotherembodiment of the invention;

FIG. 12-9 is an end view of an elbow according to an embodiment of theinvention;

FIG. 13-1 shows a swivel/vent ring according to an embodiment of theinvention;

FIG. 13-2 shows a swivel/vent ring according to another embodiment ofthe invention;

FIGS. 14-1 and 14-2 show headgear according to an embodiment of theinvention;

FIGS. 15-1 to 15-3 show various views of frame to cushion engagementaccording to an embodiment of the invention;

FIGS. 16-1 and 16-2 show a mask system according to an embodiment of thepresent invention;

FIGS. 17-1 and 17-2 show a mask system according to an embodiment of thepresent invention;

FIGS. 18-1 and 18-2 show headgear routing according to an embodiment ofthe invention;

FIGS. 19-1 and 19-2 show headgear routing according to an embodiment ofthe invention;

FIGS. 20-1( a), 20-1(b), and 20-1(c) are sequential top views of abendable or flexible forehead support according to an embodiment of theinvention;

FIGS. 20-2( a), 20-2(b), and 20-2(c) are sequential perspective views ofa bendable or flexible forehead support according to an embodiment ofthe invention;

FIGS. 21( a), 21(b), 21(c), 21(d), 21(e), 21(f), and 21(g) are variousviews of a forehead support including flexible regions according to anembodiment of the invention;

FIGS. 22( a), 22(b), 22(c), 22(d), 22(e), 22(f), 22(g), and 22(h) arevarious views of a forehead support including flexible regions accordingto an embodiment of the invention;

FIGS. 23( a), 23(b), 23(c), 23(d), and 23(e) are various views of aforehead support including flexible regions according to an embodimentof the invention;

FIGS. 24( a) and 24(b) show a forehead support wherein each side of thecross-bar includes a resilient spring arm according to an embodiment ofthe invention;

FIGS. 25 and 26 show a forehead support including a forehead padconstructed of a soft foam material according to an embodiment of theinvention;

FIGS. 27 to 32 show various views of a frame for a mask system accordingto an embodiment of the invention;

FIGS. 33 to 39 show various views of a cushion for a mask systemaccording to an embodiment of the invention;

FIGS. 40 to 45 show various views of the cushion of FIGS. 33 to 39 andthe frame of FIGS. 27 to 32 assembled to one another according to anembodiment of the invention;

FIGS. 46 to 54 show various views of an elbow and swivel for a masksystem according to an embodiment of the invention;

FIG. 55 shows a top view of a vent assembly according to anotherembodiment of the invention;

FIG. 56 is a cross-sectional view through line 56-56 of FIG. 55;

FIG. 57 is a side view of the vent assembly shown in FIG. 55;

FIG. 58 shows a mask cushion provided with the vent assembly of FIG. 55according to an embodiment of the invention;

FIG. 59 is a cross-sectional view through line 59-59 of FIG. 58;

FIGS. 60 and 61 illustrate an elbow with a vent according to anotherembodiment of the invention;

FIGS. 62 and 63 illustrate a cushion with a vent according to anotherembodiment of the invention;

FIGS. 64 and 65 are alternative views of the vent assembly of FIGS.55-59;

FIGS. 66 to 69 show alternative views of a forehead support arm andforehead support pad according to an embodiment of the invention;

FIG. 70 shows an alternative view of a lower headgear connectoraccording to an embodiment of the invention;

FIG. 71 is a front perspective view of a cushion according to anembodiment of the invention;

FIG. 72 is a rear perspective view of the cushion of FIG. 71;

FIG. 73 is a front view of the cushion of FIG. 71;

FIG. 74 is a rear view of the cushion of FIG. 71;

FIG. 75 is a top view of the cushion of FIG. 71;

FIG. 76 is a bottom view of the cushion of FIG. 71;

FIG. 77 is a side view of the cushion of FIG. 71;

FIG. 78 is a front view of the cushion of FIG. 71 showing section lines;

FIG. 79 is a cross-sectional view through line 79-79 of FIG. 78;

FIG. 80 is a cross-sectional view through line 80-80 of FIG. 78;

FIG. 81 is a cross-sectional view through line 81-81 of FIG. 78;

FIG. 82 is a cross-sectional view through line 82-82 of FIG. 78;

FIG. 83 is an enlarged cross-sectional view of a flap of theundercushion in the side of nose region of the cushion of FIG. 71;

FIG. 84 is a schematic view showing localized thickening of theundercushion of the cushion of FIG. 71;

FIG. 85 is an enlarged cross-sectional view of the undercushion in thecorner of nose region of the cushion of FIG. 71;

FIG. 86 is a schematic view showing sealing forces of the cushion asviewed from the side of the patient's nose according to an embodiment ofthe invention;

FIG. 87 is a schematic view showing sealing forces of the cushion asviewed from the front of the patient's nose according to an embodimentof the invention;

FIGS. 87-1( a) and 87-1(b) are cross-sectional views through line87-1-87-1 of FIG. 87 show deformation of the undercushion for low andhigh nose bridges;

FIG. 87-2 is a schematic view showing sealing forces of the cushion asviewed from the top of the patient's nose according to an embodiment ofthe invention, the membrane of the cushion being rolled back for thepurposes of illustration to reveal the location of the undercushion inuse;

FIGS. 88 to 93 are various views of a frame according to an embodimentof the invention;

FIG. 94 is a front view of a frame and cushion according to anembodiment of the invention and showing section lines;

FIG. 95 is a cross-sectional view through line 95-95 of FIG. 94;

FIG. 96 is a cross-sectional view through line 96-96 of FIG. 94;

FIG. 97 is a cross-sectional view through line 97-97 of FIG. 94;

FIG. 98 is a cross-sectional view through line 98-98 of FIG. 94;

FIGS. 99 to 105 are various views of a mask system according to anembodiment of the invention;

FIGS. 106 and 107 show the mask system of FIGS. 99-105 with headgear ona patient's face in use according to an embodiment of the invention;

FIG. 108 is an assembly view of an elbow according to an embodiment ofthe invention;

FIG. 109 is a cross-section view of the elbow of FIG. 108;

FIG. 110 is a side view of the elbow of FIG. 108;

FIG. 111 is a cross-sectional view through line 111-111 of FIG. 110;

FIG. 112 is a cross-sectional view through line 112-112 of FIG. 110;

FIG. 113 is a side view of an elbow according to an embodiment of theinvention;

FIG. 114 is a cross-sectional view through line 114-114 of FIG. 113;

FIG. 115 is a cross-sectional view through line 115-115 of FIG. 113;

FIGS. 116-1, 116-2, and 116-3 illustrate sealing of the cushion in thenasal bridge region according to an embodiment of the invention;

FIGS. 117 to 120 illustrate bending points or bending regions of theundercushion according to different aspects of the present technology.

FIG. 119 shows a cross-section of an undercushion or backup bandsuitable for use along the side of a nose that can provide a sealingforce into the plane of the face (arrow pointing up) and into the sideof the nose (arrow pointing to the left).

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

The following description is provided in relation to several exampleswhich may share common characteristics and features. It is to beunderstood that one or more features of any one example may becombinable with one or more features of the other examples. In addition,any single feature or combination of features in any of the examples mayconstitute additional examples.

In this specification, the word “comprising” is to be understood in its“open” sense, that is, in the sense of “including”, and thus not limitedto its “closed” sense, that is the sense of “consisting only of”. Acorresponding meaning is to be attributed to the corresponding words“comprise”, “comprised” and “comprises” where they appear.

The term “air” will be taken to include breathable gases, for exampleair with supplemental oxygen.

1. Nasal Mask System

Examples of the invention are directed towards a nasal mask system thatis easy and quick to fit (e.g., with little or no adjustment), enablereduced strap tension, is manufacturable in high volumes, provides highconsumer appeal, provides comfort and seal, provides reliable quality,unobtrusive, and/or fits a large majority of the population.

As described in greater detail below, the nasal mask system includes aframe, a sealing arrangement (e.g., a cushion) provided to the frame andadapted to form a seal with the patient's nose, and an elbow, e.g.,provided to the sealing arrangement, adapted to be connected to an airdelivery tube that delivers breathable gas to the patient. A swivel ringmay be optionally provided to couple the elbow to the sealingarrangement. Headgear may be removably attached to the frame to maintainthe nasal mask system in a desired adjusted position on the patient'sface. The nasal mask system is intended for use in positive pressuretherapy for users with Obstructive Sleep Apnea (OSA) or anotherrespiratory disorder.

While each example below is described as including a nasal interfacetype, aspects of the invention may be adapted for use with othersuitable interface types, e.g., full-face interface, nasal prongs, etc.

2. Frame

As shown in FIGS. 1-1, 1-2, and 2-1 to 2-3, the frame 20 (also referredto an exoskeleton or skeleton) is structured to maintain, stabilizeand/or support the sealing arrangement 40 (and also the elbow 70) in anoperative position with respect to the patient's face. In addition, theframe 20 is structured to attach headgear to the nasal mask system.

As illustrated, the main body 22 (e.g., see FIGS. 1-2, 2-2, and 2-3) ofthe frame 20 includes an open construction with a central opening 24 toallow the sealing arrangement 40 to communicate with or receive theelbow 70 and a side wall 26 structured to retain or otherwise engage thesealing arrangement 40. In use, the frame 20 of this example is not inthe air path, i.e., sealing arrangement 40 defines breathing cavity andis directly coupled to the elbow 70 as described below. The frame 20 maybe semi-rigid or at least allow for some flexibility. The frame 20 maybe made from a single material, a combination of materials, or acombination of the same material in varying hardnesses. The frame 20 maybe made from polycarbonate, polypropylene, nylon, clear nylon,thermoplastic elastomer (TPE), silicone, or any other suitable material.

A forehead support 30 extends from the top end of the main body 22. Theforehead support 30 may be fixed (i.e., un-adjustable), adjustable(e.g., the height or length of elongated arm may be extendable, or theangle of the forehead support may be changeable), or interchangeable(e.g., various sizes of forehead supports for different sized patientsor the elongated arm may be replaced with different various lengths ofarm). The forehead support 30 includes an elongated arm 32 and an upperheadgear connector 34 providing slots or receiving holes 35 at the freeend of the arm adapted to receive respective headgear straps in use,thus using the padding of the headgear straps rather than requiring aseparate pad. In an example, the headgear connector may be adjustable,e.g., with respect to the arm 32 (e.g., tilt or angle towards thepatient's forehead). Lower headgear connectors 36 are provided torespective sides of the main body 22, each lower headgear connector 36including an elongated arm 38 and a slot or receiving hole 39 at thefree end of the arm adapted to receive a respective headgear strap inuse. The elongated arm 38 may be bendable or selectively deformable soas to allow the arm to bend towards or away from the patient's face inuse, thereby pulling the headgear onto the patient's face, e.g.,enabling side sleeping. In an example, if the elongated arm 38 isbendable or deformable with hand pressure of the user, the elongated armmay be suitably malleable to hold the deformed shape. This feature ofthe elongated arm 38 may increase the comfort, fit and/or sealing of theembodiment. The forehead support and headgear connectors may provide anunobtrusive arrangement which extend out of the patient's line of sight.The generally thin and elongate configuration of the elongated arm 38may at least partially prevent or limit obstruction to patient's line ofsight, whilst wearing the embodiment. In an example, the elongated arm38 may be constructed of wire or a metallic alloy. However, a personskilled in the art will appreciate that other materials may be usedincluding but not limited to polymeric materials.

In an example, the arms 32, 38 may be suitably formed, shaped, orcontoured to follow the contours of the patient's face whilst avoidingthe patient's line of sight or impeding their vision. Also, the arms 32,38 may include some inherent flexibility to allow a range of adjustment.The elongated arms 32, 38 may be made from a generally inextensiblematerial such as aluminum, stainless steel, polycarbonate,polypropylene, TPE, or any other suitable material. Alternatively, theelongated arms 32, 38 may be continuous with the frame 20 and thereforemade from the same material, or the elongated arms 32, 38 may be madefrom the same material as the frame 20 but not a single piececonstruction (i.e., the elongated arms 32, 38 may be attached to theframe 20). However, wherein the elongated arm 32, 38 is made ofdifferent material from the frame 20, the elongated arm 32, 38 may besecured onto frame 20 using an alternative fixing or securing method,e.g., such as gluing. The upper headgear connector 34 may be made fromthe same material as the elongated arm 32. Alternatively, the upperheadgear connector 34 may be made from a more flexible material than theelongated arm 32 such as Hytrel™, silicone, nylon, or any other suitablematerial. The lower headgear connectors 36 may be continuous with theframe 20 and therefore made from the same material, or the lowerheadgear connectors 36 may be made from the same material as the frame20 but not a single piece construction (i.e., elongated arm 38 may beattached to frame 20). Alternatively, the lower headgear connectors 36may be made from a more flexible material than frame 20 such as Hytrel™,silicone, nylon, or any other suitable material.

The forehead support and headgear connectors may be integrally molded orotherwise attached to the main body of the frame 20. The frame 20 isconstructed from a more rigid material than the sealing arrangement 40(e.g., made of silicone, foam). For example, the frame may beconstructed of plastic (e.g., polycarbonate) and/or metal materials,e.g., relatively thin metal material.

In an example, the arms 32 and/or 38 may be relatively thin or slender(e.g., 1-3 mm). In an example, the forehead support 30 and headgearconnectors 36 may be formed of a material (e.g., metallic material)which is different than the material of the frame main body 22. In suchexample, the forehead support 30 and headgear connectors 36 may beattachable to the frame main body 22. The relatively thin or slenderarms 32 and/or 38 may reduce the overall visual impact of the mask orembodiment.

In an example, upper headgear connector 34 provides a flattened area forthe attachment of straps from the headgear. In an example, the strapsattach to the upper headgear connector 34 through two apertures 35mounted on opposed sides of the upper headgear connector 34 and thestraps are adapted to extend through the apertures and elicit a forcetowards the patient's face and effectively pull the upper headgearconnector 34 towards the patient's forehead, in this embodiment.

2.1 Alternative Frame

FIGS. 5-1 to 5-6 show an alternative embodiment of a frame 420 that isstructured to maintain or otherwise support a sealing arrangement 440(and an elbow 70) in an operative position with respect to the patient'sface.

The frame 420 may be structured to attach a headgear to the nasal masksystem. The frame 420 may be made from polycarbonate, polypropylene,nylon, or any other suitable material. A swivel ring 90 may connect thesealing arrangement 440 to an elbow 70. The swivel ring 90 may be anysuitable polymer such as polycarbonate or polypropylene. The elbow 70may be small and unobtrusive. The elbow may include a ventingarrangement 75 comprising holes or apertures for venting. The elbow 70may be made from polypropylene, polycarbonate or any other suitablematerial.

A forehead support 430 extends from a top end of the main body 422 ofthe frame 420. The forehead support 430 may be fixed (i.e.,un-adjustable), adjustable (e.g., the height or length of elongated armmay be extendable, or the angle of the forehead support may bechangeable), or interchangeable (e.g., various sizes of foreheadsupports for different sized patients or the elongated arm may bereplaced with different various lengths of arm). The forehead support430 includes an elongated arm 432 and an upper headgear connector 434providing slots or receiving holes 435 at the free end of the arm 432adapted to receive respective headgear straps in use, thus using thepadding of the headgear straps rather than requiring a separate pad. Inan example, the headgear connector 434 may be adjustable, e.g., withrespect to the arm 432 (e.g., tilt or angle towards the patient'sforehead).

Upper headgear connector, or forehead support pad, 434 may be made fromsilicone, nylon, polypropylene, TPE, polycarbonate, or any othersuitable material. Elongated arm 432 may be made from a malleable metal.The frame 420 may be a connection point for the elongated arm 432 andthe sealing arrangement 440.

Lower headgear connectors 436 are provided to respective sides of themain body 422 of the frame 420. The lower headgear connectors 436 may behook shaped. The lower headgear connectors 436 may also be integrallyformed with the main body 422 of the frame 420, or they may be formedseparately from the main body and attached by, for example, adhesive orany form of mechanical fixation.

Each lower headgear connector 436 may include a gap 439 between an upperend of the connector 436 and the main body 422 of the frame to permit aheadgear strap to be inserted therebetween. It should be appreciatedthat the headgear connectors 436 may also be connected at both the lowerend and the upper end to the main body 422 of the frame 420. Theconnectors 436 may be bendable or selectively deformable so as to allowthe connectors 436 to bend towards or away from the patient's face inuse, thereby pulling the headgear onto the patient's face, e.g.,enabling side sleeping. This may increase the comfort, fit and/orsealing of the nasal mask system. The forehead support 430 and theheadgear connectors 434, 436 may provide an unobtrusive arrangementwhich extend out of the patient's line of sight. The placement of thelower headgear connectors 436 at lower corner positions on the main body422 of the frame 420 may at least partially prevent or limit obstructionto patient's line of sight, whilst wearing the nasal mask system.

2.2 Alternative Frame

The following illustrates alternative embodiments of a frame, arm, andforehead support, for a mask system.

2.2.1 Frame

FIGS. 7-1 to 7-3 show a nasal mask system including a frame 520, sealingarrangement or cushion 540, elongated arm 532 and forehead support 530,elbow 570, and ring 590 to couple the elbow to the cushion.

As best shown in FIGS. 8-1 to 8-3, each lower headgear connector 536provided to the frame may be generally S-shaped. Each lower headgearconnector includes a top portion 536(1), a middle portion 536(2), alower portion 536(3), and a connecting portion 536(4) that attaches theconnector to the frame. The top portion 536(1) may have a lead inadapted to guide the headgear strap into position. The middle portion536(2) is adapted to abut or is close to the frame, so as to retain thestrap within the connector once it is engaged. The lower portion 536(3)is adapted to receive the strap once it has been pushed through themiddle portion. The connecting portion 536(4) allows the connector tohinge outwards or away from the frame to allow a headgear strap to passbetween the middle portion of the connector and the frame.

The connectors 536 are aligned close to the frame to enable ease of usein sliding headgear along the side of the frame. The self closingconnector enables easy access while still acting as a retention featurefor headgear.

In an embodiment, one or more portions of the connector may beconstructed of TPE.

FIGS. 8-4 and 8-5 illustrate alternative lower headgear connectors,e.g., hook-shaped connector 536-1, and connector 536-2 with free endadapted to engage a connector base 520-1 on the frame. As shown in FIG.8-5, the free end of the hook-shaped connector 536-1 includes aretaining hook to help retain the headgear strap. As shown in FIG. 8-4,the connector 536-2 may be biased into engagement with the base 520-1 tohelp retain the headgear strap.

FIGS. 16-1 and 16-2 illustrate another embodiment of a frame 520-1 forsupporting the cushion and headgear (e.g., open frame arrangement withlower cross-bars 5536 for lower headgear straps and a forehead supportbar with an opening 5537 for upper headgear straps). FIGS. 17-1 and 17-2illustrate another embodiment of a frame 520-2 for supporting thecushion and headgear (e.g., headgear clip 5540 includes opening 5440(1)adapted to engage a bar-like receptacle 5541 on frame). The frame 520-2also includes a forehead support bar with an opening for upper headgearstraps as in FIGS. 16-1 and 16-2 described above. In addition, the frame520-2 includes upwardly extending cushion support bars 521 adapted tosupport and/or retain the cushion.

In an alternative embodiment, the frame may include clip receptaclesadapted to removably interlock with respective headgear clips associatedwith lower headgear straps.

2.2.2 Elongated Arm

The frame supports the elongated arm (e.g., constructed of metal,malleable metal) that holds the forehead support.

In an embodiment, as shown in FIGS. 7-1 to 7-3, the metal arm 532 may bean encapsulated extrusion. As shown in FIG. 9-1, the metal m of the arm532 may be wider at the front so the plastic encapsulation p does notovershadow the metal. Such encapsulated arrangement provides a softtactile feature to soften and protect the metal.

In another embodiment, as shown in FIGS. 9-2 and 9-3, the metal arm maybe an exposed extrusion (e.g., polished extruded aluminum). Thisarrangement highlights the metal feature and provides a streamlined,unobtrusive design.

FIG. 9-4 illustrates an arm 532 constructed of glass filled Nylonencapsulated in a polymer coating (such as silicone, TPE). Theencapsulated metal design may be substituted with a reinforced plasticto provide strength in place of the metal and facilitate a thinunobtrusive arm. This arrangement also provides the opportunity to addcolor and finish details.

2.2.3 Forehead Support

The forehead support is supported by the arm 532. As shown in FIGS. 10-1to 10-5, the forehead support 530 may have flexible region 531 builtinto the forehead support to allow it to spring from its naturalv-shaped position or shape to a more linear position or shape. Theflexible region may be a thinned portion of material (i.e., samematerial as rest of forehead support, just thinner to allow flex), asofter, less stiff material or a combination of a softer material and athinner section when compared to the remaining portions of the foreheadsupport 530.

The flexible region may be a co-molded portion of flexible material,such as thermoplastic elastomer (may also be colored), silicone, or anyother material that may flex. The remainder of the forehead support maybe made from a less flexible material such as nylon, polycarbonate orpolypropylene. Co-molding may be via a chemical and/or mechanical bondbetween the two materials. The separately formed/assembled flexibleregion reduces breakage risk and enables assembly offsite with theheadgear. The forehead support may include a frosted finish.

In an embodiment, the forehead support 530 may first be molded flat.Then, the flexible region 531 may be molded over the forehead support530, with the forehead support 530 positioned in its in use or flexedconfiguration. This may preload or provide a bias or spring to theforehead support.

The flexible region provides an auto-adjust flex feature that isadjusted with headgear tension enabling greater biasing of the cushionto assist fit. Preferably, the forehead support may flex so as to tiltor rotate the upper portion of the mask cushion inwards and outwards ofthe patient's nasal bridge region. In one form, when the headgear strapsare tightened, the forehead support may splay outwards or flattenagainst the patient's forehead. This will tilt or rotate the maskcushion, with the lower portion of the mask cushion acting as a hingepoint. The upper portion of the mask cushion may hence tilt or rotateinwards, in a direction generally normal to the plane of the patient'sface, towards the patient's nose bridge. This may be useful to patientswho have a higher nose bridge than other patients as this will urge thenasal bridge region of the mask cushion into sealing engagement withtheir nose.

Alternatively, the forehead support may be made from a thickened,compliant material, such as foam, that can be compressed therebyachieving a similar result.

As shown in FIG. 10-2, the position of the forehead support without anyloading (i.e., natural state), may be demonstrated as angle α, e.g.,angle α may be 5-90°, e.g., 15°.

In use, the forehead support may allow about 0-30 mm of adjustment inthe anterior-posterior direction (as indicated by the arrow in FIGS.10-2 and 10-4). In an exemplary embodiment, the forehead support mayallow about 5-20 mm (e.g., about 10-20 mm, about 10-15 mm) of adjustmentin the anterior-posterior direction. This may allow for a greater fitrange of patients as it may accommodate a greater variety ofanthropometrics, particularly at the nasal bridge region.

Headgear may attach to the forehead support through loop holes 535(e.g., see FIGS. 10-1 and 10-3) or may attach through a loop througharrangement in which a slot 535-1 extends into the hole 535 (see FIG.10-6).

2.3 Alternative Embodiments of the Forehead Support

FIGS. 20-1( a) to 26 show alternative embodiments of the foreheadsupport.

One of the advantages of the forehead support is that the foreheadsupport provides a reasonable amount of adjustment without a lot ofadditional components. In a preferred example, the forehead support isall molded in one piece. Furthermore, pulling the headgear straps in theforehead region towards the back of the patient's head results in anintuitive movement of the cushion rotating it towards the nasal bridgeand potentially reducing and eliminating leak in that region.

In accordance with an example of the present technology, a mask systemis provided that includes a nasal cushion and a frame. The frameincludes a forehead support having a T-bar. The T-bar includes a mainshaft and a cross-bar. In one form, the cross-bar includes a left sideand a right side.

A mask system in accordance with an aspect of the present technologyincludes headgear. In one form, the headgear includes a left foreheadstrap and a right forehead strap. The left and right forehead straps areconstructed and arranged to engage with respective left and right sidesof the cross-bar in use, at a location distal from the apex.

In one form, the left and right side are arranged at an angle withrespect to one another that is less than about 180 degrees. In thisform, the cross-bar may be V-shaped in a top view. An apex is definedbetween the left and right side. In one form, the left and right sidesare constructed and arranged to bend or flex about the apex. In oneform, bending or flexing the sides by pulling them at their distal endscauses the angle between them to increase and causes the point ofcontact between the cross-bar and the main shaft to move closer to theforehead and to rotate the cushion.

In an alternative form, the left and right sides of the cross-bar may beU-shaped. In this U-shape, the cross-bar may have similar functionalityto the V-shaped form described above.

For example, FIGS. 20-1( a) to 20-1(c) and 20-2(a) to 20-2(c) each showsequential views of a generally U-shaped cross-bar 1034 structured tobend or flex about the apex as headgear tension from headgear straps1080 is applied to respective sides of the cross-bar. As illustrated,the forehead support starts at an extended position forward of thepatient's forehead. As the patient tightens the headgear (i.e., headgearstraps pulled outwardly from the cross-bar as indicated by the arrows),the sides of the cross-bar splay open or flex outwardly and thecross-bar moves into a substantially flat position on the patient'sforehead, which enables the cushion to be biased inwards towards thepatient's face. The slots 1035 in the cross-bar for respective headgearstraps may be positioned relatively far outward from the apex (e.g., bya distance d as shown in FIG. 20-2( c)) to improve vectors (e.g., lessforce required to pull forehead support toward the patient's head witheffective force).

Bending or flexing may be achieved by molding a cross-bar from amaterial that has a thinner middle section. In this way, the cross-barmay be more flexible in the middle section than in ends thereof.Additionally or alternatively, a cross-bar may be formed by co-molding amore rigid material (e.g., such as nylon) with a more flexible material(e.g., such as a thermoplastic elastomer).

For example, as shown in FIGS. 20-1( a) to 20-1(c) and 20-2(a) to20-2(c), the cross-bar may include an intermediate portion 1034(1)constructed of a more flexible material (e.g., flexible TPE or silicone)and end portions or sides 1034(2) constructed of a more rigid material(e.g., clear Nylon).

FIGS. 21( a) to 23(e) show alternative configurations of the foreheadsupport and cross-bar thereof. For example, FIGS. 21( a) to 21(g) show aforehead support including flexible regions 1036 positioned between morerigid regions, i.e., an intermediate portion 1034(1) and respectivesides 1034(2) of the cross-bar. The flexible regions 1036 areconstructed of a more flexible material (e.g., Hytrel®) and theintermediate portion 1034(1) and sides 1034(2) are constructed of a morerigid material (e.g., nylon). As illustrated, the flexible regions maybe embedded in the more rigid regions. Also, the flexible regions mayinterlocked with the more rigid regions by a retention feature, e.g.,dovetail interlock. FIGS. 22( a) to 22(h) and 23(a) to 23(e) showalternative configurations for interlocking or coupling the flexibleregion 1036 with more rigid regions 1034(1), 1034(2). In FIGS. 23( a) to23(e), the flexible region incorporates the sides of the cross-bar.

The forehead support and headgear are constructed and arranged so thattensioning the left and/or right forehead straps causes the main shaftto move and rotate the cushion. In this way, the mask fit may beadjusted to different facial shapes. For example, pulling the straps mayrotate the cushion towards the face, reducing leak in the nasal bridgeregion.

FIGS. 24( a) and 24(b) a forehead support wherein each side of thecross-bar includes a resilient spring arm 1037. As illustrated, aheadgear strap 1080 is adapted to loop around the spring arm, such thatthe headgear strap engages the patient's forehead with the spring armpositioned between the cross-bar and the headgear strap. In use,headgear tension may bend or flex the spring arm and cause the point ofcontact of the forehead support to move closer to the patient'sforehead.

FIGS. 25 and 26 show a forehead support including a forehead pad 1090constructed of a compliant material such as foam or gel. As shown inFIG. 25, the forehead pad may be coupled to the cross-bar 1034 by asnap-fit, e.g., forehead pad 1090 includes snap fingers 1091 adapted toengage with respective openings 1038 in the cross-bar with a snap fit.Opposing sides of the cross-bar include open-ended slots adapted toengage a headgear strap. As shown in FIG. 26, the headgear strap 1080may pass across the cross-bar 1034 and the forehead pad thereof 1090,such that the headgear strap engages the patient's forehead with theforehead pad positioned between the cross-bar and the headgear strap.

2.4 Further Alternative Frame Embodiment

A frame may be provided to the system to stabilise the cushion inposition and anchor the headgear to hold the cushion in position. Theframe may further add structure or support to the cushion.

The alternative frame 2020 shown in FIGS. 27 to 32 comprises a main body2100, forehead support arm 2400 and forehead support pad 2530.

The main body 2100 may be structured to capture or engage the cushionand lower headgear straps. Upper region 2700 engages a top or apexregion of a mask cushion. The upper region 2700 may be positioned at thesuperior or top portion of the main body 2100 on the non-patient side ofthe mask frame 2020. Upper region 2700 may also provide stability to thefront or elbow engaging portion of the cushion by adding rigidity orsupport to this region of the cushion. Lower region 2800 may bepositioned generally inferior to the upper region. The lower region 2800may engage or otherwise interface with a bottom region of a maskcushion.

Rear connector or engagement portion 2650 (see FIGS. 29 and 32) may bestructured to receive a tab or locking element on a mask cushion. Rearengagement 2650 may also assist location of the mask cushion within themask frame 2020. Rear engagement 2650 may be a cut-out or aperture. Rearconnector 2650 may be positioned on the patient side of the frame 2020.

Lower headgear connectors 2520 may be arranged to receive a loop ofheadgear. Lower headgear connectors 2520 may be generally hook or Cshaped to receive the headgear strap and maintain it in position. Lowerheadgear connectors 2520 may be attached or otherwise formed with themain body 2100 by connection 2525. Connection 2525 may allow someflexibility or hinging to enable some freedom of movement of the lowerheadgear connections 2520.

Lower headgear connectors 2520 may be formed from a flexible material,including but not limited to silicone, TPE, or any other suitablematerial. Lower headgear connectors may be formed from a combination ofmaterials such as a stiffer material to hold the shape and transmitheadgear forces to the mask, and a more flexible material to allow easyengagement and disengagement of the headgear straps. This may includecombinations of materials such as nylon and silicone. The flexiblematerial may also have a tackiness or friction to the material toprevent the headgear from sliding within the connectors. This mayinclude but not be limited to silicone. Preferably, assembly of theheadgear to the lower headgear connectors requires less force thandisassembling the headgear from the lower headgear connectors.Preferably, the disassembly force is less than 15N. Most preferably, thedisassembly force is less than 10N.

FIG. 70 shows an alternative view of a lower headgear connector 2520. Asillustrated, the generally hook or C shaped lower headgear connector2520 (constructed of a more flexible material, e.g., silicone) isovermolded or comolded with the main body connection 2525 of the mainbody 2100 (e.g., constructed of a more rigid material, e.g., nylon).Preferably, the flexible material may be silicone. Preferably, theflexible material may have a Shore A durometer of about 20-80. Mostpreferably, the flexible material may have a Shore A durometer of about40-60. Most preferably, the flexible material may have a Shore Adurometer of about 60. The connection 2525 includes a connecting portion2526 to assist in molding the connector 2520 to the connection 2525. Theconnecting portion 2526 includes retention slots 2526(1) to assist inthe interlocking or mechanical locking of the overmolded flexibleconnector 2520 with the stiffer connection 2525. Also, the connectingportion 2526 extends substantially to the height or top of the connector2520 to enhance headgear connection at the connector, i.e., stiffermaterial of connecting portion holds the shape of the connector toprevent headgear from sliding off the connector and transmits headgearforces to the mask. The flexible connector 2520 also allows easierremoval of the strap from the connector and easier connection of thestrap to the connector, e.g., connector deformable to facilitate removaland connection of strap.

As shown in FIG. 89, the lower headgear connector may provide interiorsurfaces 2521(1), 2521(2) that are angled with respect to one another byan angle α1 to help retain the headgear strap and prevent inadvertentremoval. Preferably, al may be less than 180°. Preferably, al may beabout 110-160°. Most preferably, al may be about 120-150°. Also, thespacing of the connector from the main body of the frame also helpsstrap retention. Preferably, the spacing of the connector from the mainbody may vary along the length of the connector. Preferably, the widestgap between the connector and the main body may be less than 15 mm toaid in retention of the strap. Most preferably, the widest gap betweenthe connector and the main body may be less than 10 mm to aid inretention of the strap.

As shown in FIGS. 41-44, side engagement tabs 2600 may be positioned onthe lateral flanges of the main portion 2100 and on the patient side ofthe mask frame for interfacing and supporting the mask cushion. In anembodiment, the tabs are positioned adjacent where the undercushion endsin the nasal bridge region. The tabs may form an interference fit with aportion of a cushion. The tabs may be thinner than remaining orsurrounding part of the frame. The tabs may also support the cushion sothat it is supported in sealing engagement with the sides of thepatient's nose or cheek region. Tabs 2600 provide structural support tothe flexible cushion so that it may not collapse away from the patient'sface (e.g., blowout) and therefore break seal in use. The tabs 2600 mayextend rearwardly from the arm 2400 as shown in FIG. 43.

Forehead support arm 2400 extends from the main body 2100 to theforehead pad 2530. Preferably, forehead support arm 2400 is thin (e.g.,1-5 mm, less than 10 mm, or about 1-5 mm) to avoid obstructing thepatient's vision, and structurally stable or relatively inextensible soas to support the mask in position.

Forehead support pad 2530 may include upper headgear connectors 2535 forengagement with upper headgear straps. Forehead support pad may furtherinclude a flexible region 2540 for adjustment of the distance of theforehead support pad from the patient's forehead in use. By tighteningor adjusting the upper headgear straps in the normal range of tensionwithout causing discomfort, the flexible region 2540 may flatten to pullthe forehead support pad closer to the patient's forehead. This willthen in turn tilt the main body inwards towards the patient's nosebridge, thereby pushing the mask cushion further on to the patient'snasal bridge in use. In an embodiment, the force to flatten the flexibleregion may be in the range of about 1-8 N. Preferably, the force toflatten the flexible region may be in the range of about 2-6 N. Mostpreferably, the force to flatten the flexible region may be in the rangeof about 2-4 N.

FIGS. 66-69 show alternative views of the forehead support arm 2400 andforehead support pad 2530. As illustrated, the forehead support pad 2530includes upper headgear connectors 2535 (e.g., constructed of a morerigid material, e.g., nylon) and a flexible region 2540 (constructed ofa more flexible material, e.g., silicone). The flexible region isovermolded with the upper headgear connectors 2535 and the support arm2400 (e.g., constructed of a more rigid material, e.g., nylon) so as tointerconnect the headgear connectors and the support arm and provideflexibility to the forehead support for adjustment of the distance ofthe forehead support from the patient's forehead in use.

Each upper headgear connector 2535 includes a loop hole 2536 forattaching headgear and a connecting portion 2538 to assist in moldingthe flexible region to the headgear connector. As illustrated, a slot2536-1 extends into the hole 2536 to provide a loop through arrangement.The support arm includes a connecting portion 2402 to assist in moldingthe flexible region to the support arm. The connecting portions 2538,2402 each include respective retention slots 2538(1), 2402(2) to assistin the interlocking or mechanical locking of the overmolded siliconeflexible region 2540 with the nylon headgear connectors 2535 and supportarm 2400. Also, as shown in FIG. 67, the silicone flexible region 2540is sufficiently thicker on each side of the nylon support arm 2400(e.g., 0.5 mm or more thickness on each side, e.g., 0.8 mm thicker oneach side) to enhance the interlock. In an embodiment, the flexibleregion may be thicker in the middle around the arm 2400 and tapertowards the connector 2535.

As shown in FIGS. 66 and 68, the headgear connectors 2535 and supportarm 2400 may include features to assist in molding with the siliconeflexible region 2540 and prevent flash and damage to the frame. Forexample, support arm 2400 may include a lip 2404 to aid molding of thesilicone flexible region over the nylon arm. Also, each headgearconnector 2535 may include a rounded wall 2539 (e.g., about 0.2 to 0.6mm high, e.g., 0.4 mm high) to aid molding of the silicone flexibleregion over the nylon headgear connector. In an embodiment, the wall2539 may be a crush bead that is crushed off the part when it is placedin the molding tool.

In a preferred embodiment, the headgear connectors 2535 and arm 2400 areformed separately from one another (e.g., 3 separate parts) and thenconnected to one another by the flexible region 2540. In an alternativeembodiment, as show in FIG. 69, the headgear connectors 2535 may beconnected to the arm 2400 by runners 2555 (e.g., headgear connectors andarm formed as one part) and then overmolded with the flexible region.

In an alternative embodiment, the headgear connectors 2535 may includesilicone connectors such as the lower headgear connectors 2520 describedabove.

FIGS. 88 to 93 show various views of the frame 2020 and its foreheadsupport arm 2400, upper headgear connectors 2535, flexible region 2540,and lower headgear connectors 2520. In an embodiment, as shown in FIG.91, the angle between connectors 2535 may be about 100-170°, e.g.,125-145°. FIGS. 94 to 98 show the frame 2020 of FIGS. 88 to 93 engagedwith the cushion 6540 of FIGS. 71 to 87.

3. Sealing Arrangement

The sealing arrangement 40 is structured to interface with the frame 20and form a seal with the patient's nose in use. In this example, thesealing arrangement 40 provides a nasal interface adapted to engage thepatient's face generally along nasal bridge, cheek, and upper lipregions of the patient's face. However, other interfaces are possible,e.g., full-face. The sealing arrangement provides a compliantarrangement adapted to seal relatively quickly and maintain seal in use.In an example, the sealing arrangement may be structured to seal with orwithout air pressure.

3.1 Silicone Cushion

In the example of FIGS. 1-1 to 1-4, the sealing arrangement 40 includesa cushion 42 constructed of a generally flexible material including butnot limited to silicone, TPE, gel, or other material. The cushion may bemoulded in a material having a Type A durometer of about 35 to about 45,for example, about 37 to about 42, preferably about 40. The cushion 42defines a breathing chamber or cavity adapted to receive the patient'snose and provide air communication to the patient.

The face-contacting side of the cushion 42 includes a dual-wallconfiguration wherein the cushion includes an undercushion 44 and amembrane 46 that at least partially covers the undercushion 44 (e.g.,see FIG. 1-4). The membrane is generally softer and less stiff than theundercushion and provides a seal against the patient's face in use. Theundercushion is structured to generally support the membrane and preventcollapse of the membrane when the nasal mask system is attached andtightened using the headgear. In an example, the undercushion may onlybe provided in selected regions of the mask system, e.g., along thecheek regions, or not at all. Also, the cushion may be frosted, e.g.,for easy fit and comfort, and/or tinted.

FIG. 1-4 shows a cross-section through cheek regions of theface-contacting side of the cushion 42. As illustrated, the cushionincludes a sickle-shape or question-mark configuration with a baseportion 60 and an upper portion 62 that is radially offset towards theoutside of the base portion 60, e.g., to reduce size and perceived bulk,minimize dead space within the breathing chamber, and/or add moreflexibility to the undercushion and membrane in use. Such cross-sectionmay be provided around the entire perimeter of the cushion or may onlybe provided in selected regions of the cushion. In an example, the“question-mark”-shaped cross-section in the upper lip region may includeless curvature, e.g., to avoid overhang of the cushion into thepatient's mouth and prevent nostril occlusion.

In an example, the gap or spacing 45 between the membrane 46 andundercushion 44 (e.g., see FIG. 1-4) may be adjusted, e.g., to reducewrinkling and leak. For example, the gap may be relatively small so thatthe membrane closely follows the geometry of the undercushion. In anexample, the cushion may be molded so that the gap is larger, but themembrane is preloaded to hinge closer to the undercushion after molding.In another example, a bellows 64 (as indicated in dashed lines in FIG.1-4) may be provided or molded with the membrane to bias the membranecloser to the undercushion.

The non-face-contacting or frame side of the cushion 42 includes one ormore interfacing structures adapted to interface or otherwise removablyconnect to the frame 20. In the illustrated example, the cushion 42includes one or more elongated and spaced protrusions 50, e.g., alongthe sides and bottom thereof adapted to engage or interlock withrespective openings 27 along the side wall 26 of the frame 20. As shownin FIGS. 1-1 and 2-1, such arrangement provides positive reinforcementthat the connection has been established as the user can visually seethe connection and optionally a proper connection may result in anaudible clicking noise. In addition, the cushion 42 includes a notch ordetent 52 along the top thereof adapted to engage or interlock with abead or catch along the inner side of the frame side wall 26 (notshown), e.g., to assist with alignment and even prevent misalignment.However, it should be appreciated that the cushion may be connected orinterlocked with the frame in other suitable manners.

For example, a possible arrangement for connecting the cushion 42 to theframe 20 is disclosed in U.S. Pat. No. 7,000,614, which is incorporatedherein by reference in its entirety.

The non-face-contacting side of the cushion 42 also includes an opening55 adapted to receive or otherwise communicate with the elbow 70 asdescribed below.

FIGS. 1-5 to 1-12 show a cushion substantially similar to the cushion 42described above and indicated with similar reference numerals. Incontrast, the cushion of FIGS. 1-5 to 1-12 does not include a notch ordetent along the top thereof.

As illustrated, the face-contacting side of the cushion (i.e., includingthe membrane 46 and undercushion 44) may be co-molded with or formedseparately and attached to the non-face-contacting side of the cushion(i.e., defining the opening 55 and breathing chamber). Preferably, theface contacting side of the cushion and the non-face-contacting side ofthe cushion are formed as a single component. Preferably, this singlecomponent may be made from a flexible sealing material that isrelatively biocompatible when in contact with patient's skin, includingbut not limited to silicone.

FIGS. 1-9 to 1-12 show various cross-sections through the cushion. Asshown in FIG. 1-9, the cushion may not include an undercushion in thenasal bridge region of the cushion. Also, as shown in FIG. 1-9, thecurvature and/or length of the membrane and undercushion in the upperlip region membrane is selected for fit range, comfort, and to preventocclusion of the nares. In contrast, the curvature and/or length of themembrane at the nasal bridge region may be flatter and longer than theupper lip region, e.g., to increase seal stability and fit range. Thisis because the cushion must accommodate for a variety of nasal bridgeheights including high nose bridges and flatter nose bridges, and assuch, a longer membrane at the nasal bridge region is required. There isno undercushion at the nose bridge region to allow greater flexibilityand provide less force on the sensitive region that is the nose bridge.The anthropometric variation of the patients in the top lip region isless so the length of the membrane is less than the nose bridge region.The undercushion is provided in the top lip region to aid in stabilizingthe cushion in position on the patient's face.

FIGS. 1-11 and 1-12 clearly illustrate the sickle-shape or question-markconfiguration through cheek regions of the face-contacting side of thecushion, while FIGS. 1-9 and 1-10 show the upper lip region which issubstantially devoid of such configuration. The sickle shape is requiredin the cheek regions to allow for greater flexibility of the cushion toaccommodate anthropometric variation of a patient's faces. For example,some patients may have a generally flat face and hence require thecushion to flex from its substantially curved profile to a flatterprofile. The cheek regions will be required to flex inwards ordownwards. Alternatively, for patients with angular or swept backcheeks, they may not require as much flex of the cushion. In bothscenarios, the patient's should have approximately the same level ofcomfort and hence force on their face from the cushion. The addedflexibility of the sickle shape allows for a range of deflection of thecushion with approximately the same force feedback on the patient'sface.

In addition, a lip seal 57 may be provided inwardly from the opening 55to seal against the elbow in use.

3.2 Foam Cushion with Silicone Membrane

In an alternative example as shown in FIGS. 2-1, 2-2, and 2-4 to 2-8,the sealing arrangement 40 may include a foam cushion 241 and a siliconecushion or membrane 242.

The silicone cushion 242 defines the breathing chamber and is adapted tosupport or otherwise retain the foam cushion 241. As best shown in FIG.2-6, the face-contacting side of the silicone cushion 242 provides adual-wall configuration including an undercushion 244 and a membrane246. The non-face-contacting side of the silicone cushion 242 includesan opening 255 adapted to receive or otherwise communicate with theelbow 70.

The undercushion 244 and adjacent side wall 247 extending from theundercushion 244 are structured to retain the foam cushion 241. Theundercushion 244 curves outwards from the side wall 247 and away fromthe breathing cavity to provide a channel 248, which is opposite to themembrane 246 which curves inwards into the breathing cavity. Asillustrated, at least the patient side of the foam cushion 241 isinserted into the channel 248 (e.g., see FIGS. 2-2 and 2-6) defined bythe undercushion 244 with the interior surface of the foam cushion 241supported by the side wall 247. The foam cushion 241 may be retained inposition by an interference and/or friction fit with the siliconecushion 242. The foam cushion 241 is positioned under the membrane 246and within the undercushion 244, but not in the air path or breathingchamber. In use, the foam cushion 241 may absorb forces applied to theundercushion 244, e.g., along cheek regions of the silicone membrane.

The non-patient side of the foam cushion 241 supports the foam cushion241 and hence the silicone cushion 242 on the frame 20. As illustrated,the foam cushion 241 includes one or more interfacing structures adaptedto interface or otherwise removably connect to the frame. In theillustrated example, the foam cushion 241 includes one or more spacedand elongated protrusions 250, e.g., along the sides thereof adapted toengage or interlock with respective openings 27 along the side wall ofthe frame 20. However, it should be appreciated that the foam cushionmay be connected or interlocked with the frame in other suitablemanners, or the frame may be connectable to the silicone cushionpossibly in conjunction with the foam cushion.

In an example, the outer lip 249 (e.g., see FIG. 2-5) of the siliconecushion 242 (i.e., the joint between the membrane and the undercushion)may be structured to engage with an outer edge of the frame 20 so thatthe silicone cushion 242 and frame 20 encapsulate the foam cushion 241.

In an example, a concertina or bellows-type arrangement may be providedin a nasal bridge region of the silicone cushion, e.g., to provide ahigher degree of flexibility or increased movement without compromisingseal in use. For example, the silicone cushion may include a concertinasection such as that described in PCT Application No. PCT/AU2009/000241,filed Feb. 27, 2009, which is incorporated herein by reference in itsentirety.

In an example, corrugations may be provided in the upper lip region ofthe membrane and/or undercushion of the silicone cushion, e.g., toprevent occlusion of the nares.

The foam cushion 241 may include skinned or unskinned foam. The foamcushion 241 may be open cell, closed cell, or a combination of open andclosed cells. The foam cushion 241 may be die cut, molded or compressioncut. The foam cushion 241 may be made from a polyurethane foam, siliconefoam, or any other suitable material. The foam cushion 241 may be madefrom the same material or a combination of materials, e.g., two foamswith different properties. For example, protrusions 250 may be made froma denser or harder foam than the remainder of foam cushion 241.

The cushion 242 may also be made from materials other than silicone. Forexample, the cushion 242 may be made from a TPE, gel-filled, or anyother suitable material.

3.3 One Size Fits Most Cushion

A cushion according to an embodiment of the present invention may beconstructed to fit a wide variety of patient's faces with only one size,i.e., can fit a large variety of anthropometry.

The undercushion may include slits or may be constructed of multipleindividual narrow portions or fingers that may be structured so that thefingers splay outwards when a force is applied by the user when applyingthe mask. The fingers are arranged to spread outwards thereby pressingor supporting the membrane over a greater area of the patient's face. Inaddition, the fingers may be structured to bend, flex and move intocrevices and creases of the patient's face (e.g., due to wrinkling ofthe patient's skin or at the sides of the nose where the nostrils flareoutwards), thus supporting the seal in these typically difficult to sealregions.

FIGS. 71-87 illustrate a cushion 6540 according to an embodiment of theinvention. As described in greater detail below, the cushion 6540provides a nasal interface adapted to engage the patient's facegenerally along the nasal bridge region NB, side of nose region SN(including upper side of nose and lower side of nose), nasal-labialcrease or corner of nose region CN, and upper or top lip region UL ofthe patient's face (e.g., see FIGS. 74, 78-82, and 94-98).

The face-contacting side of the cushion 6540 includes a dual-wallconfiguration wherein the cushion includes an undercushion 6544 and amembrane 6546 that at least partially covers the undercushion 6544. Inthe illustrated embodiment, the undercushion is not provided in thenasal bridge region NB, e.g., see FIGS. 79 and 95. As shown in FIG. 79for example, the free end of the membrane 6546 may include a bead6546(1). The inclusion of the bead may allow the orifice defined by themembrane to be molded into the cushion, so that no additional cutting isrequired to form such orifice. In the illustrated embodiment, themembrane includes a relatively thin thickness, e.g., about 0.2 mm toabout 0.35 mm.

The cushion may include a sickle shape in one or more regions of thecushion, e.g., see upper lip, side of nose, and corner of nose regionsin FIGS. 79-82. In use, the sickle shape of the cushion provides a hingeor flex point 6567 (e.g., see FIG. 98) to facilitate controlleddeformation of the cushion in use. Also, such sickle shape of thecushion allows one or more portions of the cushion to overhang the frame2020 (e.g., see FIGS. 95-98), which may allow the frame to support oneor more portions of the cushion as it is deformed in use. In one form,this arrangement provides a less stiff undercushion which reduces thelikelihood of the cushion bottoming out over the range of displacementsused, hence making the cushion more comfortable.

FIG. 117 shows bending points or bending regions BP of the undercushionor backup band 6544 according to an embodiment invention, and FIGS. 118,119, and 120 show bending points BP for undercushions of otherarrangements. Different cross-sections may be used in different regions.

Preferably the arrangement illustrated in FIG. 117 is used in a top lipregion of an undercushion or a backup band. This arrangement may bedescribed as a double cantilever, depending on the relative thickness ofthe different sections. Increasing the thickness increases thestiffness. The shape of the cross-section may be arranged to extendlaterally or radially outward of the adjacent sidewall, or in anotherversion such as shown in FIG. 118 may be more in line with an adjacentsidewall, and have a similar radial outer extent by arranging folds orbends inwardly of the adjacent sidewall.

Preferably the cross-section shown in FIG. 119 is suitable for use alongthe sides of the nose. This arrangement can lead to improved lateralforce being exerted to seal a difficult region of the face. Thisarrangement may be described as a triple cantilever, depending on therelative stiffnesses of the different sections.

An alternative arrangement is shown in FIG. 120 which may be describedas a single cantilever.

The non-face-contacting or frame side of the cushion 6540 includeselongated protrusions or locking tabs 6550 along the sides thereof toengage or interlock with the frame 2020 to secure the cushion inposition, e.g., see FIGS. 97 and 98. The cushion 6540 also includesraised securing tabs 6552 along lower sides thereof to interface orengage with the frame (e.g., see FIGS. 97 and 98), and a raised top tab6554 at the apex of the cushion to interface or engage with the frame.FIG. 95 shows the tab 6554 engaged with the frame 2020 to help retainthe cushion to the frame. The raised top tab 6554 may also provide aidto robotic demolding of the cushion from the mold. However, it should beappreciated that the cushion may be connected, interlocked, and/oraligned with the frame in other suitable manners.

The non-face-contacting side of the cushion also includes an opening6555 adapted to receive or otherwise communicate with the elbow. Asillustrated, the opening may provide a vent arrangement such as thatshown in FIGS. 13-1 and 13-2. However, it should be appreciated that thecushion may have alternative vent configurations, e.g., such as thatshown in FIGS. 55-59.

Nasal Bridge Region

As best shown in FIG. 79, the length or depth d1 of the membrane 6546 inthe nasal bridge region is in the range of about 10-30 mm, e.g., 15-25mm, e.g., 19-20 mm, e.g., 19.58 mm. As illustrated, the depth d1 extendsfrom about the start of the membrane (i.e., where the thin sealingportion is able to flex/hinge from the connecting portion 6547) to thetangent of the patient contacting portion. The depth d1 of the membranein the nasal bridge region is relatively larger than those in the artand has been optimized to suit variations in anthropometry. For example,relatively high nasal bridges may extend further into the membrane,whereas relatively shallow nasal bridges may rest on the membrane withlittle or no flex of the membrane.

The geometry or curvature of the membrane 6546 in the nasal bridgeregion when viewed from the top is also configured to fit a wide varietyof patient's faces. As best shown in FIG. 75 (which shows the scallop orcurvature at the nasal bridge region and raised portions 6549 at side ofnose region), the depth d2 in the nasal bridge region is in the range ofabout 10-15 mm, e.g., 11-12 mm, e.g., 11.52 mm, and the width d3 in thenasal bridge region is in the range of about 10-20 mm, e.g., 15-16 mm,e.g., 15.35 mm.

The depth d2 is sufficient to accommodate the flattest noses, such thatthe edge of the membrane will sit on the nasal bridge and the raisedportions 6549 will sit on respective sides of the nose. A higher nasalbridge will anchor on the sides of the nose at the raised portions andthe membrane at the nasal bridge region will flex to allow the nasalbridge to move into the membrane at the nasal bridge region and stopsomewhere within the zone z.

The width d3 is sufficient to accommodate wide nasal bridges. The raisedportions 6549 will anchor at the sides of the nose and then the membranewill flex or stretch to accommodate the nasal bridge. The width d3 isselected to suit the widest nose, so that the raised portion always lieson the harder, boney tissue under the eye socket so as to anchor,stabilize, and position the cushion in the desired location.

In use, in one preferred form, as the membrane or sealing flap issubstantially unsupported by undercushion in the nasal bridge region,when a nose moves into sealing position, the membrane is in tension onthe highest portion of the nasal bridge. Furthermore, it is preferably“pinched in” on the sides of the nose in the region adjacent the highestpoint of the nasal bridge. The lateral force on the sides of the nosemay be arranged to vary with height of nasal bridge. A deeper nasalbridge pushes further into the membrane, increasing the tension in thatregion, and drawing the sides of the cushion to bend, or cantileverinwards and to increase the lateral force and improving the seal on thesides of the nose. On a face with a relatively low nasal bridge, andwith high cheekbones, the region of the cushion adjacent the nasalbridge may be splayed outwards, increasing a tension force in themembrane and leading it to increase a sealing force on the relativelylow nasal bridge. In the preferred form of the present invention, thebackup-band or undercushion is relatively free to flex inwardly andoutwardly compared to prior art cushions in a region adjacent the nasalbridge. See FIGS. 116-1 to 116-3.

Side of the Nose

The undercushion 6544 at the side of the nose has been constructed so asto anchor the cushion, and position and stabilize the membrane,particularly due to curvature on the face as the nose transitions to thecheeks. This curvature can vary across patients. The undercushionpositions the membrane and maintains the profile of the membrane so thatit does not crinkle.

There is a flap or extending portion 6545 of the undercushion 6544 thatis wider than other regions of the undercushion such as the corner ofthe nose region or top lip region. This arrangement ensures that verythin noses may contact the membrane in a region where the membrane issupported by the undercushion and ensure the smooth transition of themembrane from the nose to the cheeks. Wider noses will contact a widerarea of the membrane and a larger portion of the undercushion willsupport the membrane.

FIG. 74 shows various exemplary dimensions to provide an indication ofthe approximate location of the flap 6545 of the undercushion. In anembodiment, d4 is about 5-15 mm, e.g., 9-10 mm, e.g., 9.26 mm, d5 isabout 10-15 mm, e.g., 12-13 mm, e.g., 12.80 mm, d6 is about 20-25 mm,e.g., 22-23 mm, e.g., 22.10 mm, and d7 (e.g., distance from the bottomof the flap to the top lip region) is about 10-20 mm, e.g., 15-16 mm,e.g., 15.58 mm. FIG. 75 also shows an exemplary distance d8 from the topof the flap 6546 to the approximate contact point of the cushion in thetop lip region. The cushion typically sits on the patient's top lip inabout the same place, but the place where the cushion is likely to siton the nasal bridge may vary. Accordingly, the flaps are spaced asufficient distance from the top lip region to sit on the sides of thenose.

FIG. 83 is a cross-sectional view through the widest portion of the flap6545 of the undercushion 6544. As illustrated, the flap has a relativelylarge radius so that the undercushion may roll or flex inwards easily sothat undue pressure is not exerted on the sides of the nose (e.g., suchpressure may occlude the nares or cause a pinching sensation). In anembodiment, the radius r1 of the outer face is about 12-20 mm, e.g., 16mm, and the radius r2 of the inner face is about 8-16 mm, e.g., 12 mm.Also, the thickness t1 towards the free end of the flap is about 0.5-1.5mm, e.g., 0.9 mm, to enable easy flexing, and the thickness t2 inwardsfrom the free end of the flap is about 1.0-1.5 mm, e.g., 1.2 mm, toencourage hinging rather than collapse of the undercushion.

The length of the flap 6545 is measured from the tip to the connectionof the flap to the frame or front of the cushion. The length of the flapis about 10-30 mm. Preferably, the length of the flap is about 15 to 25mm. Most preferably, the length of the flap is about 18-23 mm. Mostpreferably, the length of the flap is about 20 mm.

Crease or Corner of the Nose

The undercushion at the crease or corner of the nose has been structuredso as to stabilize or anchor the mask in this region. Also, the creaseor corners of the nose are inherently difficult to seal on as thegeometry of this region of the face can be complex, i.e., flares of thenostrils, top lip, and cheek regions come together in a depressionand/or crease of the skin. The undercushion is stiffer in this region soas to sufficiently support the membrane such that it can be positionedto abut or conform to this more complex geometry. As shown in FIG. 84(which shows the undercushion for half the cushion), the undercushion inthe corner of nose region includes localized thickening to increase itsstiffness. In an embodiment, the localized thickness t3 may be about 1-2mm thick, e.g., 1.4 mm thick. Also, FIGS. 81 and 82 show theundercushion in the corner of nose region CN, and its relatively thickerthickness and tighter radius.

FIG. 85 is a cross-sectional view through the corner of nose region ofthe undercushion 6544. In an embodiment, the radius r3 of the outer faceis about 5-15 mm, e.g., 8 mm, and the radius r4 of the inner face isabout 2-8 mm, e.g., 4.85 mm. Also, the thickness t4 at the tip of theundercushion is about 0.5-1.5 mm, e.g., 0.85 mm, and the thickness t5 atthe peak of the undercushion is about 1-2 mm, e.g., 1.4 mm. Thethickness t5 at the peak is relatively thicker to stabilize the membraneand cause hinging about this point rather than at the base b of theundercushion.

Upper or Top Lip Region

As best shown in FIGS. 79 and 95, the undercushion at the upper or toplip region UL has been configured to accommodate the sensitive mouth gumtissue. Therefore, the thickness of the undercushion in this region isabout 0.5-1.0 mm, e.g., 0.7 mm. The thickness of the undercushion in thetop lip region may be the thinnest with respect to the other regions ofthe undercushion. The radius of the undercushion in the top lip regionis relatively large with the intention that the cushion rests on the toplip region rather than anchoring. In an embodiment, the radius of thetop lip region may not be constant, e.g., radius r5 at its center isabout 65-75 mm, e.g., 72.71 mm, and radius r6 towards the corner of thenose region is about 30-40 mm, e.g., 36.85 mm.

A mask in accordance with the present technology is able to adapt thesealing forces dependent upon the size and shape of the face and nose ofthe wearer. For example, in the top lip region, the sealing forces maybe the result of both compression forces through the undercushion orbackup-band, and a tension force of the membrane or facial flap. A widernose may splay the corners of the cushion outwards and increase theamount of tension force which is applied to the face to effect a seal.Such an arrangement may be suitable for a flatter shape of face in thisregion.

Relationship Between Membrane and Undercushion

In the illustrated embodiment, the membrane may vary in its distancefrom the undercushion in different regions of the cushion, i.e., the gapbetween the membrane and the undercushion may vary in different regionsin the cushion. In regions of the facial topography where there is morediversity (e.g., such as the top and sides of the nose), a larger gapmay be provided to allow additional area for the membrane to flex. Also,in regions such as the top lip region where there is a tendency for themembrane to stretch or exert a tensile force on the top lip, a smallergap may be provided to allow less flexibility and thus more support ofthe membrane. FIGS. 76 and 79 show exemplary distances of the gapbetween the undercushion and membrane in different regions of thecushion. In an embodiment, the distance d9 is about 5.8-6.0 mm, e.g.,5.89 mm, d10 is about 4.8-5.0 mm, e.g., 4.93 mm, d11 is about 4.2-4.4mm, e.g., 4.29 mm, d12 is about 4.0-4.2 mm, e.g., 4.06 mm, d13 is about3.2-3.4 mm, e.g., 3.3 mm, d14 is about 3.4-3.6 mm, e.g., 3.49 mm, d15 isabout 3.7-3.9 mm, e.g., 3.76 mm, and d16 is about 3.7-3.9 mm, e.g., 3.76mm.

Sealing Forces

FIGS. 86 and 87 are schematic views showing exemplary sealing forces ofthe cushion as viewed from the side and front of the patient's nose inuse.

As shown in FIG. 86, the cushion in the nasal bridge region does notseal along the sellion or dip of nose indicated at A. Rather, thecushion in the nasal bridge region seals along a lower region of thenasal bridge indicated at B. Since the cushion seals lower down thenose, a relatively large cutout of the undercushion in the nasal bridgeregion is provided (e.g., see cutout 6557 in FIG. 74). That is, the noseis wider lower down the nose, so the cutout is sufficiently wide toaccommodate a wide range of patients.

The membrane in the nasal bridge region includes a stretching effect toapply force in the patient's nasal bridge, i.e., the stretch orelasticity of the membrane is used to apply force in the nasal bridgerather than the undercushion as in other regions of the cushion. Forexample, the cushion is pushed onto the patient's face until no spacingor gap is provided between the membrane and the undercushion. Because noundercushion is provided in the nasal bridge region, the membranestretches as the cushion is pushed onto the patient's face, i.e.,membrane stretches across the raised portions 6549 shown in FIG. 75. Thestretched or expanded membrane provides a taut, trampoline-like membraneportion to apply force in the nasal bridge.

For example, FIGS. 116-1, 116-2, and 116-3 illustrate sealing in thenasal bridge region NB with stretch and tension. FIG. 116-1 shows thecushion before contact with the patient's nose. As illustrated, themembrane or facial flap 6546 is spaced from the undercushion or backupband 6544. FIG. 116-2 shows the nose contacting the membrane 6546 sothat the membrane engages the undercushion, which places the membrane intension (illustrated in this figure as a point load) across the gapdefined by the undercushion in the nasal bridge region. As the nose ispushed further into the cushion as shown in FIG. 116-3, the undercushionacts as a cantilever spring and starts to bend (illustrated in thisfigure as a point load).

The surface of the membrane may be frosted or polished to createfriction and enhance the seal. Polishing the surface of the tool maygive rise to a more sticky or tacky feel and increase friction. Afrosted sealing surface may be provided by increasing the roughness ofthe surface of the tool. A frosted surface may be preferable in someregions.

As shown in FIGS. 87 and 87-2, the curved flaps 6545 of the undercushionare configured to provide a sealing force into the sides of the nose andabove the nasal vents indicated at C. The curved flaps push and/or rollin on the sides of the nose, as well as surround the nose (except in thenasal bridge region). There is no undercushion above the flaps to theapex. The gap G between the flaps is sized to fit the smallest nosepopulation, i.e., gap is sufficient narrow to ensure that the flapscontact the sides of the nose for a wide range of patients. In anembodiment, the gap G is about 10-30 mm, e.g., 15-25 mm, e.g., 18.5 mm.

As a result of the preferred relatively large radius of the flaps 6545,each flap defines a bending point for low nose bridge-type noses that issufficiently spaced from the stiff portion of the side wall. In use,each flap bends or rolls without the low nose bridge encountering thestiff portion of the side wall. FIG. 87-1( a) shows exemplarydeformation of the flap for a nose low bridge, and FIG. 87-1( b) showsexemplary deformation of the flap for a high low bridge. Thisarrangement is in contrast to undercushions known in the art which havea smaller radius which may allow a wider/low nose to encounter a stifferregion of the side wall.

As shown in FIG. 87, the thickened undercushion in the corner of noseregion provides a sealing force into the plane of the patient's face atthe crease of the nose indicated at D. This region of the face is lesssensitive and able to bear more force to stabilize the mask on thepatient's face. The seal at the crease of the nose is important fornasal cushions, in contrast to a full-face cushion which passes overthis region. Thus, the undercushion is relatively stiff in the corner ofnose or crease region to dig in at the crease and force the cushion intothe plane of the patient's face to seal and stabilize. Also, the cushionin the crease region includes a sickle shape (e.g., see FIG. 82) toprovide controlled deformation in use.

The undercushion in the lip region for providing sealing force at thepatient's upper lip (indicated at E in FIG. 86) is relatively less stiff(e.g., compared to the crease region) for comfort.

The shape, size, curl, and/or thickness of the undercushion may bevaried to vary the force in different regions of the face.

3.4 Alternative Sealing Arrangement

FIGS. 5-1 to 5-6 show an alternative embodiment of a sealing arrangement440. The sealing arrangement 440 may include a protrusion or protrusions450 that are configured to be received in openings in the main body 422of the frame 420 in a manner similar to that described above. Thesealing arrangement 440 may also include a cushion as described above.For example, the sealing arrangement 440 may include an undercushion anda membrane, or a foam cushion and a silicone cushion as described above.

The cushion may have a dual wall seal, with the under cushion at thenose bridge cut out or removed. The under cushion at the upper cheeks orsides of nose may be raised to stabilize the cushion on the face of theuser. The cushion may have a polished outer surface and matte innersurface. The cushion may be made from silicone or any other suitablematerial.

3.5 Alternative Cushion

In FIG. 11-1, each side of the cushion 540 includes a protrusion 550which provides a retention feature adapted to interlock with the framein a manner to that described above. The top end of the frame includes alanding 541 for branding and cushion retention, and each side of theframe includes a cupped section 543 to assist with retention and tie inaesthetically with the landing at the top end of the frame.

FIGS. 11-2 to 11-9 show various views of a cushion 540-1 according toanother embodiment. As best shown in FIGS. 11-8 and 11-9, theface-contacting portion of the cushion (e.g., membrane 546, undercushion544, and side wall 542) provides a sickle-shape or question-markconfiguration to enhance comfort and flexibility.

As best shown in FIGS. 11-6 to 11-9, the cushion 540-1 includes a shockabsorbing portion 545 at the front of the cushion, i.e., portion betweenseal and elbow. The shock absorbing portion is a thinned region, e.g., 1mm thick compared to other parts of the cushion that are 2 to 3 mmthick.

FIGS. 15-1 to 15-3 are various views of the cushion 540-1 engaged with aframe. Similar to arrangements described above, the cushion includesprotrusions 550 adapted to engage or interlock with respective openingsalong the side wall of the frame 520.

In an embodiment, the undercushion at the top lip region may be removedso as to prevent discomfort due to pressure on the patient's top lipwhen cushion is in use.

In an embodiment, the patient side of the cushion may include a frostedfinish and the non-patient side of the cushion may include a polishedfinish.

3.6 Further Alternative Cushion

An embodiment of a cushion 2010 is shown in FIGS. 33 to 39. The cushion2010 may be designed to fit a range of patient's in a single size. Inorder to achieve this, various regions of the cushion 2010 may betailored to flex and adjust to comfortably fit larger noses and smallernoses.

Membrane 2040 contacts and seals with the patient's face in use. Nasalbridge region 2041 is structured to abut the nasal bridge or top portionof a patient's nose in use. Nasal bridge region 2041 may be elasticallydeformable such that it may stretch over the patient's nose in use.Raised side portions 2042 may engage and compress on the sides of thepatient's nose proximal to the patient's eyes in use. This compressionforce may stabilize the cushion into engagement at the sides of thepatient's nose. The compression force may also mean that on wider noses,the nasal bridge region 2041 will stretch over the patient's nasalbridge. Alternatively, nasal bridge region 2041 may rest or abut thepatient's nose without stretching. Furthermore, the nasal bridge region2041 is deeper or longer so that patient's with high nasal bridges canposition their nose on the membrane and flex the nasal bridge region2041 of the membrane over their longer nasal bridge in use.

Side flaps 2043 are longer or extend further into the mask cushion sothat the cushion may seal with a flatter or shallow nose in use. Sideflaps 2043 may be flexible so that they can flex into the cushion if thepatient has a higher nose bridge.

Peaks 2046 on the membrane may be raised portions or points of greaterheight when compared to other regions of the membrane. This may be tosecure the cushion in the corners of the user's nose proximal to thenostrils or flares of the nares in use.

Upper lip region 2044 is positioned on the lower portion of the membraneand may engage or rest on the user's top lip in use. The curvature maybe swept to conform to various top lip geometries of patients.

Flexible portion 2045 may be positioned proximal to the connection ofthe elbow or swivel ring on the cushion 2040. Flexible portion 2045 maybe a region of thinned material or more flexible material to allowdecoupling of the tube from the cushion.

Locking tabs 2601 may be positioned on at least one portion of the frontregion of the cushion. Locking tabs 2601 may have raised profile orpeaks that secure the cushion in position when assembled with a frame.

Securing tabs 2661 may also be positioned on at least one portion of thefront region of the cushion. Securing tabs 2661 may also be higher thanother portions of the cushion to interface other otherwise engage with aframe.

Top tab 2651 may be a raised portion positioned at the apex of thecushion. Top tab 2651 may be positioned to allow for easier robotdemolding of the cushion and also to engage with a frame.

Vent or swivel ring 2090 may be positioned at an orifice of the cushionto receive an elbow or supply of breathable gas. Vent ring 2090 may bemolded or otherwise permanently attached with the cushion 2010. Ventring 2090 may have vent holes around at least a portion of the perimeterto permit the exhaust of gases from the mask system.

FIGS. 40 to 45 show the cushion 2100 and the frame 2020 described aboveassembled to one another according to an embodiment of the presentinvention.

4. Elbow

The elbow 70 includes a first end portion 72 and a second end portion74, e.g., see FIGS. 1-2, 2-2, and 2-5. The first end portion 72 providesan interfacing structure structured to interface or otherwise attach tothe sealing arrangement 40. The second end portion 74 is adapted to beconnected to an air delivery tube. The first portion is angled about135° with respect to the second portion. However, the first and secondportions of the elbow may have other suitable angles with respect to oneanother, e.g., 0°, 90°, 120°, etc.

In an embodiment, the elbow may be similar to that disclosed in PCTApplication No. PCT/AU2008/001557, filed Oct. 22, 2008, which isincorporated herein by reference in its entirety.

4.1 Elbow Connection to Sealing Arrangement

The sealing arrangement 40 is structured to maintain the elbow 70 in anoperative position with respect to the patient's face. That is, thesealing arrangement may act as a carrier and bearing surface for theelbow 70. The sealing arrangement and elbow may connect with a frictionfit, snap-fit, mechanical interlock, or other suitable attachmentmechanism. However, other suitable arrangements for attaching the elbowto the sealing arrangement are possible.

In the illustrated example, a swivel ring 90 is provided to couple theelbow 70 to the sealing arrangement 40. Such swivel ring 90 is anoptional component, and it should be appreciated that the elbow 70 maybe directly coupled to the sealing arrangement 40 without the swivelring.

As best shown in FIG. 2-5, the swivel ring 90 includes an annular groove92 along its outer circumference adapted to interlock with the annularflange 256 defining the opening 255 of the silicone cushion 242 (oropening 55 in the cushion 42 of FIGS. 1-1 to 1-4). The innercircumference of the swivel ring 90 provides a relatively smooth annularsurface 94 adapted to engage the exterior surface of the first endportion 72 of the elbow 70. The free end of the first end portion 72provides an annular bead 73 to engage the interior shoulder of theswivel ring 90, e.g., with a snap fit. Such connection holds the elbowin place (e.g., preferably a relatively airtight connection) and permitsrotation or swiveling of the elbow with respect to the sealingarrangement.

The swivel ring is constructed from a more rigid material than thesealing arrangement (e.g., made of plastic, silicone, foam). Thisarrangement may facilitate connection of the elbow, e.g., hard elbow tohard swivel ring rather than hard elbow to soft sealing arrangement. Inan example, the swivel ring may be co-molded, mechanically overmolded,and/or chemical bond overmolded with the sealing membrane or cushion,e.g., to reduce parts. Alternatively, the swivel ring may be provided asa separate part, e.g., to allow disassembly.

Also, the region of the cushion surrounding the opening 55, 255 mayinclude some flexibility to allow decoupling of the elbow from theremainder of the mask system, e.g., to reduce tube drag. For example, adecoupling mechanism between the cushion opening 55 and the elbow 70 mayinclude a flexible gimble or membrane on the cushion 42 in the region ofthe opening 55. A similar decoupling mechanism is described in U.S.patent application Ser. No. 12/379,940, filed Mar. 4, 2009, which isincorporated herein by reference in its entirety. The thickness of thegimble region may be ⅓ the thickness of the cushion adjacent the gimbleregion. Preferably, the thickness of the gimble may be less than ⅓ thethickness of the cushion adjacent the gimble region. Most preferably,the thickness of the gimble region is less than ½ the thickness of thecushion adjacent the gimble region. FIGS. 79, 96, and 98 show anotherexemplary gimble region 6565 at the front of cushion 6540 between theseal and elbow opening. As illustrated, the gimble region is includesthicker and thinner regions with the thinner region towards the elbowopening.

The sealing mechanism between the cushion and the elbow may be similarto that described in U.S. Patent Publication No. US 2006/0201514, whichis incorporated herein by reference in its entirety.

FIGS. 4-1 to 4-4 show alternative arrangements for coupling the elbow 70to the cushion 42. In FIG. 4-1, the cushion 42 includes an interferencelip seal 57 inwardly from the opening 55 adapted to seal against an endof the elbow 70 in use. FIG. 4-2 illustrates alternative sealingarrangements for the lip seal 57 of FIG. 4-1. As illustrated, the lipseal 57(1) may seal against the end of the elbow 70, e.g., like thearrangement of FIG. 4-1. Alternatively, the lip seal 57(2) may bearranged to seal around the perimeter of the elbow 70. FIG. 4-3 showsthe elbow 70 attached to the cushion 42 via a swivel ring 90 asdescribed above. In this embodiment, the cushion provides an inwardlyextending, interference lip seal 57 adapted to seal against an end ofthe elbow 70 in use. FIG. 4-4 shows an arrangement in which the swivelring 90 provides an inwardly extending lip seal 91 adapted to retain theelbow 70 and/or seal around the perimeter of the elbow 70 in use.

In examples, a swivel may be provided to the second end portion of theelbow and adapted to be connected to the air delivery tube. FIG. 4-5shows one example of a swivel 95. FIGS. 4-6 to 4-9 show alternativearrangements for forming a seal between the elbow 70 and the swivel 95.As shown in FIG. 4-6, a lip seal 96 may be provided (e.g., overmolded)to an interior surface of the swivel 95 for sealing with the elbow. Asshown in FIG. 4-7, the swivel 95 may include flange portions 97(1),97(2) adapted to overhang respective ends of the elbow 70. In thisembodiment, the elbow 70 defines a channel 71 for receiving andretaining an end of the swivel 85. In FIG. 4-8, the end of the swivel 95includes a resilient clip portion 98 adapted to clip onto a flange 73 ofthe elbow 70. Also, a lip seal 96 may be provided to an interior surfaceof the swivel 95 for sealing with the elbow 70. The lip seal 96 may bestructured such that is biased into engagement with the elbow 70 in use.FIG. 4-9 shows a swivel 95 in which an internal lip seal 96 is formedseparately from the swivel 95 and attached thereto, e.g., by spin weldor glue.

4.2 Vent Arrangement

As shown in FIGS. 1-1 and 1-2, the elbow 70 includes a vent arrangement75 for gas washout. The vent arrangement 75 includes a plurality ofholes (e.g., 5-100 holes, e.g., 20-50 holes, or about 45 holes). Asshown in FIG. 2-5, each hole may include a contour or taper along itslength. However, it should be appreciated that the vent arrangement mayinclude other suitable arrangements, e.g., different number of holes,hole arrangement, vent insert with one or more vent holes, etc.

The vent may also, for example, be a diffuse vent as disclosed in U.S.Patent Publication No. US 2009/0050156, which is incorporated herein byreference in its entirety.

4.3 Alternative Elbow

FIGS. 12-1 to 12-3 show various views of an embodiment of a non-ventedelbow and FIGS. 12-4 to 12-8 show various views of another embodiment ofa non-vented elbow. Each elbow 570 includes a cushion connection end570(1) adapted to connect to the cushion and a tube connection end570(2) adapted to connect to the air delivery tube. In FIGS. 12-4 to12-8, sides of the elbow provide “button” points or flexible fingers 573for the user to grab and quick release the elbow from the cushion.

As best shown in FIGS. 12-4 to 12-8, the elbow includes a flexibleregion 571 (constructed of soft and tactile TPE or flexible polymer)that may be co-molded with a more rigid region (constructed of polymersuch as polypropylene or polycarbonate). The flexible region allowsportions of the elbow to flex inwards when the patient pinches orsqueezes these regions, enabling disengagement of the cushion connectionend from the mask.

The arrangement also enables sealing of the elbow, a soft touch featurethat adds value, some color to the part to make it more appealing, andeasy assembly.

As shown in FIG. 12-9, there may be stoppers 575(1) within the elbow toprevent the flexible regions from occluding the air path in use. Asupport beam 575(2) may also be provided to the inside of the elbow toprovide strength to the annulus of the elbow, and also to maintain thestoppers in position.

In an embodiment, a TPE portion may be molded onto the cushionconnection end of the elbow to enable better seal and ease of rotationof the elbow when connected to the cushion.

The use of a vent ring as described below enables the elbow to benon-vented.

In an embodiment, the elbow may include a frosted finish.

4.4 Swivel/Vent Ring

The swivel/vent ring is provided to provide an interface between thecushion and elbow, i.e., allow elbow to connect to the cushion. As shownin FIG. 13-1, the ring 590 provides an interface 591 for cushionconnection, an interface 593 for elbow connection, and vent holes 595along the perimeter of the ring to provided diffused venting. In anembodiment, the ring may be co-molded (by either chemical or mechanicalretention) with the cushion.

The ring provides ease of flow tuning (i.e., possible to add or removevent holes), improved CO₂ washout, control of humidificationrequirements, greater diffusivity, unobtrusiveness, ease of elbowmanufacture since no vent holes in elbow, and/or facilitates aestheticfreedom in the elbow.

In an embodiment, a lip seal may be provided (e.g., co-molded) with thering. For example, as shown in FIG. 13-2, the ring may be molded withchannels 596 between the vent holes 595 on the patient side, and thenthe vent ring may be placed in the tool for making the cushion and asthe material to create the cushion is filled into the tool, some of thecushion material will flow through the channels between the vent holesto form a lip seal 597. The lip seal 597 may provide a more effectiveseal between the cushion 540 and the elbow 570. Molding the lip seal inthe vent ring is beneficial to reduce parts for the patient to handle.

In an embodiment, the ring may be non-venting (i.e., no vent holes) foruse with non-vented mask embodiments or vented elbows.

4.5 Alternative Elbow and Swivel

FIGS. 46 to 50 show an embodiment of an elbow 3000 and swivel 3500.

The elbow 3000 includes a first portion 3010 adapted to connect to amask (e.g., vent ring 2090 of cushion 2010 described above) and a secondportion 3020 provided to the swivel 3500 adapted to connect to an airdelivery tube. In an embodiment, the swivel (e.g., constructed of nylon)may be overmolded to the elbow (e.g., constructed of polypropylene),e.g., second portion of elbow includes stepped shoulder 3030 for swivelovermolding and tooling shut off. However, the swivel may be connectedto the elbow in other suitable manners, e.g., snap-fit. An annular ring3600 is provided to the swivel, which provides a stop for connecting theair delivery tube.

The first portion includes a flexible quick release mechanism forattaching the elbow to the mask, e.g., vent ring 2090 of cushion 2010.The mechanism includes a button 3100 on one or both sides of the firstportion and a groove 3200 surrounding each button that allows the buttonto flex with respect to the first portion. The button is raised for easeof use and pinch travel. The profile shape of the button may change,e.g., for function and/or tooling. Also, each button includes a tab orcatch 3040 adapted to engage the vent ring 2090, e.g., with a snap-fit,to releasably secure the elbow to the cushion 2010.

Moreover, at least a portion of the button is constructed of a soft,tactile material (e.g., TPE), e.g., to aid ease of use. As best shown inFIGS. 49, 53, and 54, a channel 3070 is provided between the buttons toallow flow of TPE or soft tactile material. Also, interior stops 3300are provided to prevent the buttons from being pressed too far into theelbow cavity and possibly breaking.

As illustrated, upper and lower tabs 3050 are provided to the firstportion to interface with the vent ring 2090 and prevent the elbow frompushing too far into the vent ring.

FIGS. 108-112 show alternative views of the elbow. FIG. 108 shows theovermolding of the swivel 3500 to the elbow 3000, and then theovermolding of the buttons 3100 to the elbow. As illustrated, the elbowincludes a retention catch 3040, a bearing surface 3041 to facilitaterotation relative to the cushion, a sealing edge 3043 for sealing withthe cushion, and an insertion stop 3045 (provided on top, bottom, andsides of the first portion of the elbow) that provides a stop forconnecting the cushion. FIG. 109 shows an interior stop 3300 to preventa respective button from being pressed too far. As shown in FIGS. 110and 111, the button 3100 may include a step 3101 (e.g., 0.85 mm orgreater) along its perimeter that overhangs the elbow. Such stepprovides a flat even section for button movement in use. In analternative embodiment, as shown in FIGS. 113 and 114, the step may bethinner (e.g., 0.35 mm). As shown in FIG. 112, the button may include agenerally thin (e.g., about 0.4 mm thick) and concave section 3103 alongits perimeter to facilitate button depression. Section 3103 may beformed from an elastomer such as TPE or silicone. Section 3103 may sealthe buttons to the elbow body so as to seal the air path through theelbow. In an embodiment, the depression force F may be less than about10 N. In an alternative embodiment, as shown in FIG. 115, the concavesection 3103 may be thicker 3103 (e.g., about 1.3 mm) which may increasethe depression force. It should be appreciated that the thickness of theconcave section may be tuned to adjust the force.

As noted above, venting for the mask is provided by the vent ring 2090.This arrangement provides several advantages, e.g., ease of flow tuning,improved CO₂ washout, control of humidification requirements, greaterdiffusivity, unobtrusive, ease of elbow manufacture, and/or facilitatesaesthetic freedom in the elbow.

5. Alternative Vent Assembly

FIGS. 55 to 59 show an alternative vent 4000 that may be molded into orwith another part of the mask assembly. An embodiment of the presentinvention relates to an assembly of interconnected vent structuresjoined together by element or structure in a first position that can bedeformed to cause the vent structures to move to a second position.

An embodiment of the present embodiment relates to a vent 4000 beingmolded into a cushion 4500, however it is possible for vent 4000 to bemolded into any other part of the mask assembly in the air path, forexample a tube, an elbow or a frame.

Vent 4000 may comprise a first structure to interconnect the ventarrays, where if the shape of the first structure is changed thearrangement or position of the vent arrays is also changed.

FIG. 55 shows an embodiment of vent 4000. The first structure maycomprise a stem 4100 and/or at least one branch 4150. Stem 4100 maysupport the array of vent branches 4200. Stem 4100 may be central to thebranches 4150. Stem 4100 may position and/or maintain branches 4150 in adefined spacing or array. Stem 4100 may also be structured to aidalignment of the vent 4000 with respect to the cushion 4500 or othermask system element (e.g., elbow, frame, etc.).

The embodiment of stem 4100 shown in FIG. 55 has a ring or circularstructure. It should be appreciated that stem 4100 may have analternative configuration such as a rectangle, triangle or any othershape that meets the desired outcomes of positioning and aligning thevent 4000 in the mask system and spacing the branches 4150.

Stem 4100 may have an aperture 4600. Aperture 4600 may be constructedand arranged to receive a portion of the mask system. For example, asbest shown in FIGS. 58 and 59, aperture 4600 is located to receive anelbow of a mask system.

Branches 4150 may connect the stem 4100 to the vent arrays 4200.Branches 4150 may be evenly spaced about stem 4100 or may have analternative configuration. The spacing of branches 4150 may beconstructed to position vent arrays 4200 such that they achieve diffuseexiting air flow streams.

In another embodiment, branches 4150 may be selectively deformable.Branches 4150 may be formed into a first position by molding, cutting orany other forming method. Branches 4150 may then be deformed by heating,cooling, force, or other method into a second position. In anembodiment, branches 4150 may be deformed by placing vent 4000 into atool for a mask component, closing the tool such that shape of the toolforce the branches to bend or otherwise deform, and injecting orotherwise adding a second material into the tool and allowing thissecond material to set or stabilize around the vent 4000 so as tomaintain branches 4150 in their deformed position.

In an embodiment, the second position or deformed position of thebranches may be 0-120° from the first position. In an embodiment, thesecond position or deformed position of the branches may be 30-90° fromthe first position. In an embodiment, the second position or deformedposition of the branches may be 40-60° from the first position. In anembodiment, the second position or deformed position of the branches maybe 45° from the first position.

In another embodiment, stem 4100 may be selectively deformable. Stem4100 may be formed into a first position by molding, cutting or anyother forming method. Stem 4100 may then be deformed by heating,cooling, force, or other method into a second position. In anembodiment, stem 4100 may be deformed by placing vent 4000 into a toolfor a mask component, closing the tool such that shape of the toolforces the stem to bend or otherwise deform, and injecting or otherwiseadding a second material into the tool and allowing this second materialto set or stabilize around the vent 4000 so as to maintain stem 4100 inits deformed position.

In an embodiment, the second position or deformed position of thebranches may be 0-120° from the first position. In an embodiment, thesecond position or deformed position of the branches may be 30-90° fromthe first position. In an embodiment, the second position or deformedposition of the branches may be 40-60° from the first position. In anembodiment, the second position or deformed position of the branches maybe 45° from the first position.

As best shown in FIGS. 55 to 57, branches may connect to at least onevent array 4200. Vent array 4200 may comprise a body 4240 and at leastone vent hole 4250.

As best shown in FIGS. 56 and 57, body 4240 may be generally rectangularor any other shape that may accommodate the at least one vent hole 4250.Body 4240 may also comprise a ledge or protrusion 4230 that may assistin mechanically bonding or locking the vent 4000 in position when formedwith the mask component, such as cushion 4500.

In an embodiment, there is at least one vent hole 4250 on each body4240. In the illustrated embodiment, as shown in FIG. 55, four ventholes 4250 are arranged on each body 4240. However, any number of holesis possible, for example, 1, 5, 10, 11, or more holes.

In an embodiment, vent holes 4250 may be convergent, that is, theirentrance may have a greater diameter than their exit. In an embodiment,their exit diameter is about 0.1-2 mm. In an embodiment, the exitdiameter is about 0.3-0.8 mm. In an embodiment, the exit diameter isabout 0.7 mm. In an embodiment, the vent holes have an aspect ratio ofapproximately 1:3.

FIGS. 58 and 59 show the vent 4000 arranged in cushion 4500. Vent arrays4200 are distributed around aperture 4600. FIG. 59 shows thelongitudinal axis 4155 of branch 4150 disposed at an angle α to the axis4610 of aperture 4600. Hence, vent holes 4250 on body 4240 are arrangedto position exiting air flow streams from vent holes 4250 at an angle αwith respect to the aperture 4600, hence splaying or dispersing theindividual air stream exiting each vent hole. This diffuses the air flowpaths and thus reduces the jetting of air streams onto a bed partner orbed clothes. This arrangement may also reduce vent noise.

In alternative embodiments, a similar vent 4000 may be arranged in anelbow, whereby the vent 4000 is formed in a first position, then placedin the mold for an elbow. In the mold for the elbow, the branches andvent arrays are deformed approximately 90° from their first position,thereby being positioned around the circumference of a portion of anelbow. The material for the elbow component is then injected into themold and set, thereby maintaining the vent 4000 in the desired position.

The vent 4000 may be constructed of a material that is flexible and/orextensible. The vent 4000 may be constructed of nylon, polypropylene,thermoplastic elastomer, silicone, polycarbonate, polyurethane or anyother moldable, selectively deformable polymer.

The mask component into which the vent is formed may be made from amaterial with a lower melting point than the material used for the vent.This is so that when the vent is inserted into the mold for the maskcomponent, and the second material for the mask component is injected orotherwise inserted into the mold, the vent does not melt.

FIGS. 64 and 65 show alternative views of the vent 4000 arranged incushion 4500. As illustrated, the vent arrangement allows multiple ventholes 4250 to be molded in the line of draw on a plastic cushion ring,and then bent during an over-moulding process to create a very diffuseand quiet vent array about the elbow 3000. This array is encapsulatedand suspended in the silicone material of the cushion 4500.

FIGS. 99 to 105 show various views of a nasal mask system 6600 includinga frame 6620 (e.g., like that shown in FIGS. 88 to 93), cushion 6640(e.g., like that shown in FIGS. 71-87 with the vent of 55-59 and 64-65),and elbow 6670 (e.g., like that shown in FIGS. 46-50) according to anembodiment of the invention. FIGS. 106 and 107 show the mask system 6600with headgear 6680 on the patient's head in use, e.g., headgearincluding upper side straps 6682 routed over the ears and lower sidestraps 6684 routed under the ears. In an embodiment, the mask system maybe used with headgear described in U.S. Pat. No. 7,509,958 and PCTApplication No. PCT/AU2009/001605, each of which is incorporated hereinby reference in its entirety.

Alternative Vents

FIGS. 60 and 61 illustrate an elbow 6000 with a vent 6050 according toanother embodiment of the invention. In the illustrated embodiment, thevent 6050 includes a vent plate 6052 having one or more vent holes 6054formed within it. The vent plate also includes a weakened or bendableregion 6056 (i.e., hinge). A swivel 6070 may be provided to the elbowfor attachment to an air delivery tube. Each vent hole may include acontour or taper along its length. However, it should be appreciatedthat the vent may include other suitable arrangements, e.g., differentnumber of holes, hole arrangement, etc.

In an embodiment, the vent plate 6052 may be molded with the vent holes6054 and the hinge 6056. Then, the vent plate may be placed in the moldfor the elbow 6000. As the mold for the elbow closes, the hinge of thevent plate allows the vent plate to bend from a first position (as shownin FIG. 60 which shows the vent plate in a generally upright position inthe elbow mold) to a second, in use position (as shown in FIG. 61 whichshows the vent plate bent into engagement with the elbow). Once the moldfor the elbow is closed, the material for the elbow is injected into themold and the vent plate remains in its second, in use position by themolded elbow. Also, additional components may be molded onto the elbow(e.g., elbow buttons 6060 as shown in FIG. 61).

FIGS. 62 and 63 show a vent 6150 according to another embodiment of theinvention. In this embodiment, the vent 6150 is in the form a ventinsert that is molded (e.g., over-molded) with the cushion 6140. Thevent insert is positioned along a top portion of the cushion above theopening adapted to receive the elbow. As illustrated, the vent insertincludes a plurality of vent holes 6152 that are oriented to directexhausted gas away from the patient's face in use. In addition, the ventholes may be arranged to diffuse exiting air flow streams. It should beappreciated that the vent may include other suitable arrangements, e.g.,contoured vent holes, different number of holes, hole arrangement, etc.

6. Headgear

Headgear may be removably attached to the headgear connectors 34, 36 ofthe frame 20 to maintain the nasal mask system in a desired position onthe patient's face. In the illustrated example, the frame provides afour-point connection for a pair of upper headgear straps and a pair oflower headgear straps. However, the frame may provide otherarrangements, e.g., two-point connection or three-point connection.Rigidizers or reinforcing materials may be provided to one or more ofthe straps.

Headgear may be constructed of an elastic or flexible material such aswoven and non-woven fabric, TPE, polypropylene, nylon, or any othersuitable material. The headgear may also be reinforced with stiffeningmembers that may add stability.

In an example, the nasal mask system may be used with headgear such asthat described in Australian Provisional Application Nos. AU 2008906390,filed Dec. 10, 2008, and AU 2009900327, filed Jan. 29, 2009, each ofwhich is incorporated herein by reference in its entirety. In anexample, attachment/adjustment of such headgear may be provided bybuckles or hook and loop material. For example, the headgear straps maybe constructed of a nylon elastic material with strap adjustmentprovided by buckles without any hook and loop material.

However, the nasal mask system may be used with alternative headgeararrangements. For example, FIGS. 3-1 to 3-79 illustrate headgear straparrangements and headgear connection arrangements according toalternative examples of the present invention.

FIGS. 3-1 to 3-4 illustrate alternative arrangements for sizing theheadgear straps. FIG. 3-1 shows a headgear with two part top strapadjustment. Each side of the top strap 5001(1), 5001(2) may be adjustedby a ladder lock or buckle connected at the mask, or Velcro™ adjustment,or any other suitable means. This arrangement provides centraladjustment, can be evenly tensioned, and provides a greater fit range.In addition, the rear portion of the headgear straps may be narrowed orwidened by sliding the rear straps 5003 (shown generally vertical, butmay be otherwise angled) over the lower headgear straps 5004. FIG. 3-2shows a headgear with a single top strap 5001 and a single lower strap5004. The top and lower straps may preferably be constructed from anelastic or other suitable stretchy material, so as to provide a widerange of fit. This arrangement may also provide minimal to no adjustmentand no requirement of a buckle or extraneous parts on the mask system.FIG. 3-3 shows a headgear with an adjustable top strap with sides5001(1), 5001(2) where a buckle 5002 is provided to one side of the topstrap, such that the adjustment of the top strap length is independentof the mask (i.e., forehead support). This may provide advantages suchas one adjustment point, and low profile. FIG. 3-4 shows a headgear withone piece top strap 5001 with adjustment and an alternative buckle 5002.This buckle may be hinged at one end (e.g., hinge 5002(1)), such thatwhen it is positioned perpendicular to the headgear strap, the buckleteeth 5002(2) are disengaged from the strap 5001 thereby allowing thestrap to pass through the buckle and adjust the length in use. When thebuckle 5002 is positioned parallel to the headgear strap, the buckleteeth 5002(2) engage with the strap 5001 and prevent it from slidingthrough the buckle, thus locking or fixing the length of the top strap.Such an arrangement may provide advantages such as one adjustment pointand simple clasp mechanism.

FIGS. 3-5 to 3-7(b) illustrate alternative arrangements for sizing thebottom or lower headgear straps. FIG. 3-5 shows a lower strap 5004overlapping such that at its end, the overlapped end 5004(1) wouldslidably engage with a lower headgear connector. The lower strap end maybe threaded through an adjustment buckle 5005, such that sliding of thebuckle along the length of the lower headgear strap may adjust theamount of overlapping of the lower strap hence adjusting its length inuse. Such an arrangement may advantageously provide a simple adjustmentmechanism and no requirement for traditional adjustment means such ashook and loop. FIG. 3-6 shows a lower strap 5004 overlapping such thatat its end, the overlapped end would slidably engage with a lowerheadgear connector. The lower strap end may be attached along the lengthof the lower strap material using hook and loop attachment (e.g., thelower strap headgear material is loop material, and a portion 5004(2) atthe end of the lower strap is hook material). Such an arrangementadvantageously provides a simple hook and loop connection and slim line.FIGS. 3-7( a) and 3-7(b) show an adjustment arrangement that could beutilized anywhere on the headgear, however more preferably at the top orlower headgear straps. The adjustment arrangement may include a pushthrough mushroom shaped connector 5010 that resides on one portion ofthe headgear, that may engage with a selected hole 5012 in anotherportion of the headgear so as to prevent sliding adjustment of theheadgear portions. Advantageously, this arrangement may still allow theheadgear portions to rotate over one another. Additionally, thisarrangement may have a positive feedback (e.g., clicking noise) when theadjustment arrangement is locked in position, meaning the patient willknow when their headgear is adjusted. One or more holes and/or one ormore mushroom shaped connectors may be provided to the headgear. Theadjustment arrangement may be constructed from a flexible andsufficiently hard material, such that the arrangement maintains itsconnection once in use, for example TPE, silicone, polycarbonate or anyother suitable materials.

FIGS. 3-8 to 3-13(b) show alternative fixed or adjustable headgeararrangements. FIG. 3-8 shows a headgear strap size adjustment, where aloop of material 5014 with a hole 5014(1) is provided to allow slidingengagement with a headgear strap 5004 (e.g., lower strap). The headgearstrap may be provided with one or more mushroom shaped connectors 5016to interface or engage with the hole 5014(1) provided to the loop ofmaterial. Preferably, size indicators (e.g., S, M, L or 1, 2, 3, 4, 5,etc.) may be provided on or near the mushroom shaped connectors tospecify the size that the headgear has been adjusted to. Thisarrangement may be advantageous since it provides a simple, knownadjustment mechanism and an ability to know what size the headgear hasbeen adjusted to. FIG. 3-9 shows back strap size adjustment (that may beadapted for use with a top strap, rear strap, or any other headgearstrap) where the back strap 5006 may be provided with markings 5007 toindicate size (e.g., S, M, L, XL, etc). The manufacturer, patient orother suitable person may choose which size to adjust the headgear strapto, align the adjustment markers (for example, by folding or cutting thestrap to align the markers) such that the headgear is positioned tomatch the chosen size, and then the headgear strap may be permanentlyfixed in this position using stitching, ultrasonic welding, or othersuitable technique. Such an arrangement provides no adjustment oncepermanently fixed, and a low profile connection. FIG. 3-10 shows acentre back strap 5008 constructed from an elastic or other suitablyflexible material, with adjustable arms similar to those shown in FIGS.3-7( a) and 3-7(b), i.e., mushroom shaped connector 5010 and hole 5012arrangement. FIG. 3-11 shows headgear with two positions for top strapadjustment, i.e., a hook and loop connection 5015 and a mushroom shapedconnector and hole arrangement 5016 (e.g., like that shown in FIGS. 3-7(a) and 3-7(b)). This arrangement allows for greater adjustability andmay thus accommodate varying sizes of patient's heads. FIG. 3-12 shows aheadgear connection where a first headgear strap 5004 (such as a lowerstrap) may be slidably engaged with a second headgear strap 5003 (suchas a rear strap). The second headgear strap 5003 may be provided with aloop or additional layer of material 5003(1) that is ultrasonicallywelded, stitched, or otherwise attached to the second headgear strap.The first headgear strap is positioned in the spacing or channel betweenthe second headgear strap and the additional layer of material. Theultrasonic weld or stitch or other attachment means may include bumps orprojections that provide more friction in the channel between the secondheadgear strap and the additional layer of material, to preventexcessive sliding of the first headgear strap through the channel. Theadditional layer of material may be the same as the headgear material,or a more durable component such as a TPE or silicone. FIGS. 3-13( a)and 3-13(b) show sliding clip adjustment, where the headgear strap 5018is looped through the clip 5020 and may be adjusted by engaging ordisengaging an internal spring by pressing the button 5020(1) on theclip. The end of the headgear strap may be provided with a hole 5018(1)for attachment to a frame or forehead support. This hole may bereinforced (e.g., with laminate, stitching, or other reinforcing means)whereby the reinforcement 5018(2) prevents the hole from propagating andmay also prevent the sliding clip from sliding off the headgearmaterial.

FIGS. 3-14( a) to 3-14(h) show alternative arrangements for sizing ofthe headgear straps. In embodiment, the strap may be ultrasonicallywelded, may include ultrasonically cut holes, or may be ultrasonicallymodified.

FIG. 3-15 shows a similar arrangement to FIG. 3-8, with a differentshape mushroom connector 5016 to interface with a hole 5014 (i.e.,generally square shaped).

FIGS. 3-16( a) and 3-16(b) show alternative arrangements to FIGS. 3-8and 3-15, whereby a similar sizing indicator is used, however theheadgear straps are routed differently. A first end 5021(1) of a firstheadgear strap is looped through a first side of a second headgear strap5022. A second end 5021(2) of a first headgear strap is looped through asecond side of a second headgear strap 5022. Either the first or secondend of the first headgear strap may have a size indicator on it. Thesecond headgear strap may have a hole 5023 or other means to display thesize indicator on the first headgear strap.

FIGS. 3-17 to 3-24 show alternative arrangements of headgear connectionsto the frame or forehead support. FIG. 3-17 shows a bottom strap 5024that may wrap around an arm or hole 5025 in the frame and thenre-connects to the bottom strap with button or hook and loop material.This arrangement may provide a simple, intuitive connection, with thepotential for multiple adjustment positions should multiple connectionsbe provided, slim line design, and easy to manufacture. FIG. 3-18 showsa bottom strap 5024 that may have a hook shaped clip 5025 (e.g., madefrom plastic or other suitable material) welded, sewn or laminated atone or both ends of the bottom strap material. The hook may snap into areceptacle 5026, slot or hole on the frame. Such a connecting means mayprovide a simpler drop in connection, slim line, and be easy tomanufacture. FIG. 3-19 shows a headgear strap 5024 with a series offingers 5027 positioned at the end of a strap, that may be welded orsewn or otherwise attached. The frame may also be supplied with similarfingers 5028 such that when the fingers on the headgear strap areinterlocked or overlaid onto the fingers on the frame, lateral movementand hence sliding of the headgear strap away or towards the frame isprevented or minimized. Disengagement of the fingers in the direction ofthe fingers may be relatively simple when compared to disengagement oftypical headgear clips (for example, headgear clips provided to a ResMedMirage Quattro™). FIGS. 3-20( a) and 3-20(b) show a headgear strap 5024that may have a T-bar 5029 provided at its end(s). The T-bar may beconstructed from a flexible material such as a TPE, silicone,polycarbonate, or any other suitable material. The T-bar may be attachedby looping the headgear strap through a hole provided to a T-barconnecting rod. Alternatively, the T-bar may be welded, sewn,ultrasonically welded or attached by any other suitable means. The T-barmay loop over or around a receptacle or catch 5030 provided on theframe. FIG. 3-21 shows headgear strap with a push-fit connection means5031 attached at its end(s). The push-fit connection means may beconstructed from a generally flexible material such as silicone or TPE.The push-fit connected means may be attached to the headgear strap bysimilar means described for the T-bar shown in FIGS. 3-20( a) and3-20(b). The push-fit connection means may be a bulbous shaped rod thatmay engage with holes or slots 5032 on the frame. Multiple holes orslots may be provided to the frame. FIG. 3-22 shows a headgear strap5024 looped over at its end and sewn or otherwise re-attached to itselfalong its length. The looped section is slidably engaged around areceptacle 5033 in the frame. Hook material may be provided on thelooped section of the headgear strap to enable adjustment and thenfixation of the headgear strap. The headgear material may need to beconstructed of a looped material to enable engagement of the hookmaterial. FIG. 3-23 shows a headgear strap 5024 that loops over a notchor barb 5034 on the frame. The headgear strap may be adjusted by asliding sprung clip 5035 whereby a spring mechanism within the clipenables engagement and disengagement with the headgear strap. FIG. 3-24shows headgear connection hook 5036 with slotted receptacle to allow forthe headgear strap to feed into it.

FIGS. 3-25( a) to 3-30 show alternative arrangements of headgearconnections to the frame. FIGS. 3-25( a) and 3-25(b) show a headgearstrap with an ‘R’ shaped clip 5037 attached at its end(s). The ‘R’shaped clip may be sprung or biased such that it preferably remains inits locked position. A loop 5038 may be provided to the frame (forexample, a lower headgear connector as shown in FIGS. 3-25( a) and3-25(b)) that engages with the ‘R’ shaped clip (cross section shown).FIGS. 3-26( a) and 3-26(b) show a headgear strap with a slot or cylinder5039 provided at its end(s), that slots over a frame extension or finger5040. FIG. 3-27 shows open ended headgear strap receptacle 5041 that maybe provided to a frame that enables a loop of headgear strap to be woundor looped vertically, however the slit provided at the front of thereceptacle. FIG. 3-28 shows a generally shaped headgear connectionreceptacle 5042 on the frame. Such an arrangement may be preferable forvertical insertion of the headgear strap loop 5043 (as indicated by thedrawing). Once the headgear strap loop is inserted into the headgearconnection receptacle, the headgear strap loop may pass from one side ofthe ‘U’ shaped receptacle to the other and as such, may preventaccidental disassembly of the headgear strap loop from the headgearconnection receptacle since the headgear strap loop is anchored in the‘U’ shape. FIG. 3-29 shows hook or loop material 5044 attached directlyon the frame to interface with opposing hook or loop from a headgearstrap. FIG. 3-30 shows a magnetic attachment where a magnet 5045 isprovided to the frame and a magnet 5046 is provided to the headgearstrap. FIGS. 3-31( a) and 3-31(b) and FIG. 3-32 show alternativearrangements for headgear attachment positions on the frame. FIGS. 3-31(a) and 3-31(b) show headgear attachment receptacles or slots 5047located on the perimeter of the frame, which reduces the visual bulk ofthe mask. FIG. 3-32 shows headgear mount receptacles 5048 located on theframe and adapted to receive headgear clips 5049 associated with theheadgear strap, similar to that disclosed in U.S. Pat. No. 6,374,826,which is incorporated herein by reference in its entirety.

FIGS. 3-33 and 3-37 show alternative arrangements for attaching thecushion to the frame or the lower headgear straps to the frame. FIG.3-33 shows headgear connection loops 5050(1) located at the end ofheadgear connection arms 5050(2). This arrangement may space theconnection of the headgear away from the frame, thereby allowing a morestreamlined look. FIG. 3-34 shows a skeleton frame 5051 that ispositioned along or within grooves in the cushion 5052, i.e., connectsto the cushion with an interference fit or snap fit. The skeleton framemay have headgear connection arms 5053 with a generally perpendicularpost at its end to enable a looped connection with a headgear strap. Itmay be preferable to create the skeleton frame from a more rigidmaterial than the cushion. FIG. 3-35 shows a lower headgear connectingportion 5054 positioned to snap or otherwise interface with the cushion5055 underneath or below the aperture where the elbow connects. FIGS.3-36( a) and 3-36(b) show snap fit lower headgear connection assembly5056; a variation of that shown in FIG. 3-21. FIG. 3-37 shows elbow sealring 5057 with combined headgear attachment arms 5058 that snaps orotherwise interfaces with a frame 5059 and/or cushion 5060.

FIGS. 3-38 to 3-49(b) show alternative arrangements for connecting aheadgear to a forehead support or a forehead support arm to a foreheadsupport cushion. FIG. 3-38 shows a male buckle 5061 that may snap fit toa female buckle 5062 mounted on a forehead support arm (push torelease). Headgear may be looped or otherwise connected to the malebuckle. Alternatively, the male and female buckle positions may bereversed. The buckle may be made from a suitably rigid material so as toallow for a snap fit, for example polycarbonate, polypropylene, nylon,etc. FIG. 3-39 shows a forehead support cushion 5063 with a slot orfemale connector 5063(1), that may be engaged or interfaced with a rodor male connector 5064(1) attached to a forehead support arm 5064. Thisarrangement may allow for some horizontal rotation that may bepreferable or desirable to patients. There may also be a permanent orremovable retention feature for connection of the male and femalecomponents. FIG. 3-40 shows an alternative buckle arrangement includinga male buckle 5061 and a female buckle 5062 to that shown in FIG. 3-38.FIG. 3-41 shows an alternative arrangement of male and female connectors5064(1), 5063(1) to that shown in FIG. 3-39. FIG. 3-42 shows anotheralternative arrangement of male and female connectors 5064(1), 5063(1)to that shown in FIG. 3-39. FIG. 3-43 shows a forehead support cushion5065 for attachment with upper headgear straps. The forehead supportcushion may have a slot or cavity 5065(1) to receive a T shaped foreheadsupport arm 5066. Such an arrangement may allow rotation of the foreheadsupport arm vertically and thus greater flexibility to adjust the maskin use. FIGS. 3-44( a) and 3-44(b) show a forehead support cushion 5067with a slot 5067(1) to receive a sliding engagement with a foreheadsupport arm 5068. The forehead support arm may vertically slide into theslot, and may be provided with retention tabs to prevent accidentaldisengagement of the connection. The forehead support arm may have agenerally T-shaped cross section that may prevent horizontal rotation ofthe forehead support arm when connected to the forehead support cushion.It may also act to strengthen the forehead support arm. FIG. 3-45 showsa forehead support cushion 5069 with a keyhole shaped aperture 5069(1)that may receive a forehead support arm 5070. The forehead support armmay have a generally round disk 5070(1) attached at its end forcommunication with the aperture on the forehead support cushion. Such anarrangement may allow for horizontal rotation of the forehead supportarm in use. FIGS. 3-46( a) and 3-46(b) show a forehead support cushion5071 that may have generally C-shaped pocket 5071(1) that may capture aball 5072(1) attached to the end of forehead support arm 5072. FIG. 3-47shows two piece forehead support cushion including first and secondpieces 5073(1), 5073(2) that may snap around a generally cylindricalforehead support arm 5074. FIGS. 3-48( a) and 3-48(b) show two pieceforehead support cushion that may have a first side 5075(1) thatslidably engages with a generally cylindrical forehead support arm 5076,and a second side 5075(2) that receives the end of the forehead supportarm and first side. FIGS. 3-49( a) and 3-49(b) show a forehead supportcushion 5077 that may have a two piece construction, where each foreheadsupport cushion is permanently or removably attached to the upperheadgear straps. The forehead support cushions 5077 may also haveapertures 5077(1) to receive a ball 5078(1) attached to the end of theforehead support arm 5078 to rotatably engage with the forehead supportarm. Alternatively, the ball/aperture arrangement may be reversed asshown in the related cross-sectional view.

FIGS. 3-50( a) to 3-69(b) show alternative arrangements for connectingheadgear to the forehead support with no buckle. FIGS. 3-50( a) and3-50(b) show an upper headgear strap 5079 that may be threaded throughan aperture in a forehead support 5080. In addition, the aperture may beprovided with a lip or engagement tab 5080(1) on the outer ornon-patient contacting side of the forehead support to maintain theupper headgear strap in position. FIG. 3-51 shows an upper headgearstrap 5079 that may thread through the forehead support 5080 with anengaging tab or hook 5080(1) to anchor the upper headgear strap withinthe forehead support. The forehead support may have an aperture for theupper headgear strap to rest within. FIGS. 3-52( a) to 3-52(c) show aflexible forehead support 5081 that can flex vertically away from theforehead of the patient to allow for a greater range of fit. FIGS. 3-53(a) and 3-53(b) show an upper headgear strap 5082 that may be threadthrough a forehead support 5083 which may have two engagement arms5083(1), 5083(2) to encompass and maintain the position of the upperheadgear strap. These two arms may be generally C-shaped when viewedfrom the side. FIG. 3-54 shows upper headgear straps 5084 that may bethreaded through a generally Y-shaped forehead support 5085. The slot orgap in the top of the forehead support may be provided for disengagementof the headgear straps. FIG. 3-55 shows an upper headgear strap 5086that may be provided with a pocket or gap 5086(1) such that the foreheadsupport 5087 may be inserted within the pocket of the upper headgearstrap. FIG. 3-56 shows an upper headgear strap 5088 that may have loopmaterial 5088(1) on its outer or non-patient contacting side. Theforehead support 5089 may have a facing of hook material 5089(1) thatmay interface with the upper headgear strap, thereby engaging theforehead support with the upper headgear strap. FIG. 3-57 shows an upperheadgear strap 5090 that may have a receptacle 5090(1) in its structure.The receptacle may be a gap in the fabric or an inserted reinforcingsuch as a small tube. A forehead support 5091 may be generallycylindrical and may push fit or slide into the receptacle for engagementof the forehead support with the upper headgear strap. FIGS. 3-58( a)and 3-58(b) show a forehead support 5092 with a hinged region 5092(1)that may enclose over an upper headgear strap 5093, gripping said upperheadgear strap and retaining it within the clamp. FIG. 3-59 showsforehead support 5094 that may be ultrasonically welded to an upperheadgear strap 5095. The forehead support may be permanently attached tothe upper headgear strap by other reasonable means such as gluing. FIG.3-60 shows a two piece upper headgear strap 5096 in a baseball cap stylethat may thread through a forehead support 5097. FIG. 3-61 shows anupper headgear strap 5098 with button or push pin 5098(1) that engageswith a slot or receiving portion 5099(1) on the forehead support 5099.FIG. 3-62 shows an upper headgear strap 5101 with a cylindrical section5101(1) that may engage with a forehead support 5102 that may be shapedlike a cradle or hook, such that the forehead support anchors over thecylindrical section of the upper headgear strap. FIG. 3-63 shows anupper headgear strap 5103 with a cylindrical section 5103(1) that mayengage with a Y-shaped forehead support 5104. The Y-shaped foreheadsupport may wrap around the cylindrical region of the upper headgearstrap and may include pins adapted to engage within respective openingsin the cylindrical region. FIG. 3-64 shows an upper headgear strap 5105with the end region of each end of the upper headgear strap folded intoa T-shape. This T-shaped fold 5105(1) may then be slid into a buckle orreceiving portion 5106(1) attached to the forehead support 5106. FIG.3-65 shows an upper headgear strap 5107 with a two piece slidingadjusting channel that may have an aperture or hole 5107(1) forreceiving a projection 5108(1) on the forehead support 5108. FIGS. 3-66(a) and 3-66(b) show an upper headgear strap 5109 that may be slid orotherwise engaged with a channel 5110(1) formed on the top of a foreheadsupport 5110. Alternatively, the forehead support 5111 may be slid orotherwise engaged within receiving channels in the ends of the headgear5112. FIG. 3-67 shows forehead support 5113 attached to an upperheadgear strap 5114, with the arm of the forehead support including aportion for snapping or otherwise attaching onto the frame 5115. FIG.3-68 shows forehead support 5116 sewn into a loop at the end of upperheadgear strap 5117, and the forehead support then snaps or otherwiseconnects onto the frame 5118. FIGS. 3-69( a) and 3-69(b) show a foreheadsupport with separatable arms 5119. In an embodiment, the arms may beconnected by an elastic strap 5120.

FIGS. 3-70( a) to 3-76 show alternative arrangements of bucklearrangements to be used to attach the upper headgear connectors to thestraps of the headgear. Preferably, the buckles (shown in FIGS. 3-70( a)to 3-76) are adapted to form ladder-type locking clips. In theseexamples, the strap of the headgear is weaved through a first and secondaperture in the buckles. The apertures are adapted to be in parallel andare generally aligned with the orientation of the strap, to be received.The weaving of the strap through this series of apertures allows thestrap to be secured or locked in position so as to prevent or limitslipping. The straps may also include a contoured or rippled surface tofacilitate better engagement with the buckle. Further, FIGS. 3-70( a)and 3-70(b) show an example of a buckle 5130 wherein the series ofparallel apertures (also named a ladder lock) includes a series teeth orripples 5131 on an extended end of the buckle. In an example, theextended end is kinked away from the horizontal plane to allow for orfacilitate better access by a patient's fingers which may be necessaryto disengage to the buckle, when the strap is secured. FIGS. 3-71( a)and 3-71(b) show a further example of a buckle 5132 wherein the lengthof a buckle has been configured into a curved or arcuate shape (whenviewed from the side). This also improves the ability of a user toremove or engage the strap, depending on the circumstances. FIG. 3-72shows a further example of a buckle 5133 that may be used with any ofthe above-described examples. This example of a buckle includes afurther series of teeth or engagement means 5134 positioned so as tocome into frictional contact with the strap, when in use. These secondseries of teeth are generally aligned with the general orientation ofthe engagement of the strap. This second series of teeth are generallyadapted to prevent or limit slippage of the strap, when engaged. FIG.3-73 shows a further buckle 5135 wherein the series of apertures,referred to in FIGS. 3-70( a) and 3-70(b) and 3-71(a) and 3-71(b) and3-72, are joined to form a single aperture 5136. The single aperture isadapted to receive a strap and allow it to be weaved around the buckleto prevent or limit slippage. Further, the aperture is opened or brokenat the upper surface to permit easier threading or weaving of the strap.FIGS. 3-74( a) and 3-74(b) show a further example of a buckle 5137wherein the buckle is ultra-sonically welded to one end of a headgearstrap 5138. The other end of the strap or another strap may be threadedor weaved through the apertures of this buckle. It is noted that othermeans of fixing the buckle to an end of the strap may achieve the sameor similar result, including frictional locks, gluing, or other kinds ofsuitable welding. FIGS. 3-75( a) and 3-75(b) show a further buckle 5139wherein the piece 5139(1) of the buckle positioned between the twoapertures is slightly raised. This feature of raising the centre of thebuckle may further prevent or limit slippage by increasing thefrictional forces impacted on the strap 5140, when in use. FIG. 3-76shows a further buckle 5141 wherein the buckle is attached to an end ofa first strap 5142(1) through a first set of two apertures. The firststrap is weaved through the first set of apertures and looped back ontoitself. The first strap may then be secured against itself by stitching.This buckle also includes a second set of two apertures positioned onthe opposed end and this second set may be used to engage a second strap5142(2). In an example, the second set of apertures is adapted toreleasably secure the second strap wherein the first set of apertures isrelatively more permanent and may generally prevent releasability of thefirst strap.

FIG. 3-77 shows headgear including a rear strap loop 5143(1), upperstraps 5143(2) extending from a top of the rear strap loop, and a lowerstrap loop 5143(3) that wraps around the mask and a bottom of the rearstrap loop. The length of the lower strap loop may be adjusted by aspring loaded clip 5144. FIG. 3-78 shows an adjustment arrangementincluding a mushroom shaped connector 5145 provided to the mask that isadapted to engage with a hole 5146(1) provided to a headgear clip 5146for a headgear strap. FIG. 3-79 shows an adjustment arrangementincluding a ladder-lock buckle 5147 provided to the mask that allows aheadgear strap 5148 to loop therethrough.

FIGS. 6-1 to 6-12(b) illustrate headgear connection arrangements (e.g.,buckle clip designs) according to alternative examples of the presentinvention. FIG. 6-1 shows an outrigger-type clip 5150 having a narrowconfiguration with clip arms 5150(1) adapted to be pushed along thesides to release. The neck of the clip may be flexible. FIG. 6-2 showsan outrigger-type clip 5151 including a clip arm 5151(1) adapted to bepushed down from the top to release. The neck of the clip may beflexible. The clip provides a relatively flat, low profile design. FIG.6-3 shows a continuous clip 5152 with a flexible neck. The clip includesclip arms 5152(1) adapted to be pushed along the sides to release. Theclip includes no gaps to jam into the clip receptacle. FIG. 6-4 shows aclip 5153 with a hook-like attachment portion 5153(1) adapted to engagea bar-like receptacle on the frame. FIG. 6-5 shows a clip 5154 with aflexible neck ball or tapper lead in 5154(1) and clip arms 5154(2)adapted to be pushed along the sides to release. FIG. 6-6 shows a T-bartype clip 5155 adapted to engage a hook-like receptacle 5156. The neckof the clip may be flexible. FIG. 6-7 shows a ball in socket arrangementin which the ball 5157(1) on the end of the outrigger 5157 is adapted toengage a c-cup receptacle 5158 provided to the frame, e.g., with a snapfit. In an embodiment, the receptacle (e.g., plastic) may be constructedof a harder material than the ball in socket arrangement (e.g.,silicone). FIG. 6-8 shows a loop over arrangement in which an opening5159(1) on the end of an outrigger 5159 is adapted to engage a bar-likereceptacle 5160 with an enlarged head 5160(1). FIG. 6-9 shows furtherdetails and alternatives of the clip 5151 shown in FIG. 6-2 describedabove, e.g., receptacle 5161 on frame to receive clip. FIGS. 6-10( a)and 6-10(b) show an arrangement wherein the frame includes a releasemechanism 5162 and the outrigger 5163 has a ball and catch detail5163(1) for retention. The tension of the straps may be used forrelease. FIG. 6-11 shows further details and alternatives of the clip5152 shown in FIG. 6-3 described above. FIGS. 6-12( a) and 6-12(b) showan arrangement wherein the frame includes a flexible receptacle 5164 andthe outrigger 5165 includes a push button release 5165(1).

6.1 Alternative Headgear

As shown in FIGS. 14-1 and 14-2, headgear 580 may include a two tonecolor combination (e.g., blue and grey) to assist ease of use inindicating which orientation the headgear should be when fitting themask (e.g., two tone color provides intuitive ease of use indicatingwhen headgear is correctly aligned and where hook and loop tabs arepositioned). For example, the grey or lighter color may be arranged onthe inside of the headgear so that when the headgear straps are threadedthrough the mask and fold over on itself, the grey faces the outside tobe visually less unobtrusive on the face.

The headgear provides an arrangement that looks easy to use (inherentstability structure, two-tone alignment indication), looks comfortable(no hard ridgidized parts visible, soft fabric finish, ‘soft’ greys),does not look obtrusive (soft gender neutral greys, greys sympathetic tometal and silicone colours in system, provides a high quality look andincreased value perception (two-tone colors, premium heat transferbranding, new manufacturing methods), and looks unique (departure fromtraditional breathe-o-prene style, high quality edge treatment, greyshelp emphasize branding).

FIGS. 18-1 to 18-2 and 19-1 to 19-2 show alternative arrangements forrouting the headgear straps on the patient's head in use, e.g., upperside straps 5560 routed over the ears and lower side straps 5570 routedunder the ears.

While the invention has been described in connection with what arepresently considered to be the most practical and preferred embodiments,it is to be understood that the invention is not to be limited to thedisclosed embodiments, but on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the invention. Also, the various embodiments described abovemay be implemented in conjunction with other embodiments, e.g., aspectsof one embodiment may be combined with aspects of another embodiment torealize yet other embodiments. Further, each independent feature orcomponent of any given assembly may constitute an additional embodiment.In addition, while the invention has particular application to patientswho suffer from OSA, it is to be appreciated that patients who sufferfrom other illnesses (e.g., congestive heart failure, diabetes, morbidobesity, stroke, bariatric surgery, etc.) can derive benefit from theabove teachings. Moreover, the above teachings have applicability withpatients and non-patients alike in non-medical applications.

1-112. (canceled)
 113. A nasal cushion for a mask system, comprising: aside wall defining a breathing chamber; an undercushion extending fromthe side wall; and a membrane that at least partially covers theundercushion, the membrane is adapted to seal along the nasal bridge,sides of nose, corners of nose, and upper lip of the patient's face inuse; the undercushion is only provided along the side of nose, corner ofnose, and upper lip regions of the cushion, the undercushion includes aflap or extending portion in each side of nose region that is wider thanthe other regions thereof and adapted to engage and provide a force intothe sides of the patient's nose in use.
 114. A nasal cushion for a masksystem, comprising: a cushion perimeter providing a plurality ofregions, each region being specifically configured to seal along oraround the nose, and each region having characteristics that are atleast partially determinative of the sealing force, stabilization, forcedistribution, comfort, and/or fit range provided by the cushion.
 115. Anasal cushion according to claim 114, wherein the cushion includeslateral regions configured to provide a sealing force into the sides ofthe patient's nose, a lower region to provide a sealing force into theplane of the patient's face, and an upper region that is stretchable toaccommodate the patient's nasal bridge region.
 116. A nasal cushionaccording to claim 114, wherein the cushion includes at least tworegions.
 117. A nasal cushion according to claim 114, wherein thecushion includes four regions.
 118. A nasal cushion according to claim114, wherein the cushion includes nasal bridge, side of nose, corner ofnose, and upper lip regions adapted to seal along the patient's nasalbridge, sides of nose, corners of nose, and upper lip. 119-150.(canceled)